Trapper John left because Wayne Rogers wanted to move onto other thingsMuch the same with McClain Stevenson..That being the reason for most of the departures.

What is indeed a real shame is the missed opportunity with Frank's character we saw so many on the show grow and mature; why not Frank Burns? How much of a coup would it have been that, if over the course of the series, Frank's super-patriot character came to question the authority he always followed blindly? It would have been good allegory for what was happening in American at the time (both the series' run and the 1950s).
I loved Henry's timeframe in the show, but I really liked Potter's interactions with Burns. A lot more could have grown from that.
I also would love to have heard Frank utter, near the end of the series, the line "I've only been here two years but it feels like ten."

Trapper's leaving was explained that while Hawkeye was on leave in Tokyo -a few weeks after Henry left and got killed- Trapper got his orders that he was being sent home.
Hawkeye tried to make it to the air base in time to say goodbye, but Trapper's plane had already left.
As for Ogden Stier's character -Major Charles Emerson Winchester III- he was quite different from Burns. In the first place, while Burns was a whining, weaselly character, Winchester was just snobbish and snooty. Secondly, Burns was an utterly incompetent surgeon. Winchester, however, was described as an absolutely brilliant surgeon -he was supposed to be at least Hawkeye's equal. So, Winchester was tolerated much more readily than Burns because he was such a good surgeon -the other doctors might have disliked his personality, especially at first, but tolerated him because of his surgical skills. (In one episode, Potter says to him "Winchester, you a silo full of smugbut you sure know how to use a scalpal"). As well, Winchester didn't just get offended when Hawkeye and BJ insulted him. He would give back as much as he took. And finally, Winchester was shown to have a humane side with both patients and other staff members that he occasionally let show. (I won't 111cgive anything away, but two episodes in particular stand out. One deals with a patient who has a bad stutter. Another is a patient who was a concert pianist before the war, but an injury to his hands ends his career and Winchester wants to help him).
The only time Frank ever really showed a human side was when Margaret got engaged. He starts to lose it, until Radar defuses it by placing a call to Burns' mother. Frank gets on the phone and sadly tells her that -as usual- nobody likes him and someone he thought was his friend, actually wasn't. The friend only pretended to like himthe way Frank's father used to pretend. It's the first time you see the human side of Frank and that maybe there's a reason for the way he acts. I think that if they'd developed the character more from there, Linville might have stayed.

Haha, actually, after I made that post, the next early-morning episode showed Part 1. Part 2 miraculously followed the next day. THEN, they went back to the beginning for some reason! It's a bit frazzling, if you ask me, lol. I thinkor hopethat I get a chance to buy all the available seasons on DVD, to make my life easier =D.
It's kinda sad that the cast changed so earlyand so much, too. Would you have liked it better if there were more seasons with Col. Blake and Trapper John? (Though I DO like Col. Potter very much as well.)

Yup, they do address Trapper leaving, though he's not in that episode, and BJ joining. It was the first episode of Season 4, and I think it might have been a two-parter, so you might have missed the first half of it.

This is the one main thing that I hate about MASH.They didn't give certain characters enough character development. Hawkeye Pierce, being the centrifugal character, received the best plot lines. I'd say Radar got many good ones (Thankfully!) and plenty of attention. Potter and Blake had fairly good development toobut Potter more, by far. Also, naturally, Hot Lips received much plot attention and character development as well. They should've given Blake more at firstmaybe Stevenson would've stayed longer if they had. But the good thing is, he left high and mightilywith a tragic, but ultimately effective, ending. Still, they could've done more, don't you think? Luckily, Morgan as Potter was a refreshing substitute for Blake's positionand proved so by staying all that time.
Trapper John definitely should've had much more attention paid to him. He was such an important character in the movie, being Hawkeye's major confidante, and I think he deserved better. I always liked their relationship, and it was sad that I just learned today it ended right after Blake's character was written out. (I'm kind of lost as to how they explained his leavingmaybe I missed something, I don't know. If someone could fill me in, I'd be quite happy =D. Thank you.) But Rogers should've lasted another few years, at least. It's a pity. But they made him seem more bland, I suppose, than Hawkeyebut I always saw more anyways. BJ Hunnicutt was a cool guy, but apparently, he wears out his welcome (I wouldn't know that yet, since I've just begun watching it.) towards the end.
Also, naturally, I agree with you about Frankhe certainly could've had better character devlopmentlet alone much at all! You knowfeel conflicted about cheating on his wife back home, question his morality, buddy up with Hawkeye, and either Trapper or BJ, once in a while, but always being Frank at times too, etc. The only real times he had any good attention was when his neuroses concerning Margaret got the best of himlike that time he tore apart her quarters, searching for his love notes to her.hehe. If only he had more like that.at least Linville did his best to make him an appealing and loveable guy, and IMO, because of him, I was able to care more about Frank's character and find his bumbling, religious fanatic of a Major to be a core element of the show's appeal. I don't know much about the "blowhard", played by Ogden Stiers, that replaced his position, so I can't comment. I also wonder now what Swit's Hot Lips did after Linville left.I have theories about her and Alda's Hawkeye getting together or something, but I DON'T WANNA KNOWyet, that is. It's just a curious theory that I haveI'll learn what really does happen eventually.
And I saw that Burghoff left a few years before the show ended, so I'm really anxious to see up to that season and figure out why he did. AGAIN, I DON'T WANT TO KNOW AHEAD OF TIMEjust to let you know, lol. But I just can't imagine "MASH" without RadarI -LOVE- him. He is by far my favorite characterand his quirkiness is just delightful (I'm scaring myself right now.). In time, I'll learn that too, much to my disappointment.
Sorry for rambling on like this, but if anyone has taken the time to read this or skim through this, please let me know if you agree about how certain characters didn't receive the character development they deserves. I understand that it was the '70s (and early '80s) and all, and writers were still maturing on TV at a much slower pace than in films, but they still should've been more aware.Also, if anyone could clear up my confusion about Trapper John's departure. You see, last night on TV, I saw the episode when Blake's character was "written-out". Immediately following that was the episode where Potter's character is written-in to replac111ce Burns as the leading Commander. Now, I'm pretty sure that Blake leaving was the season finale of Season 3.so, when Potter joins the crew, is that the beginning of Season 4? Or did they leave out a few episodes? Because if they didn't, then I can't believe they didn't even explain Trapper's departure.but that wouldn't make sense, because they also couldn't explain BJ's introduction.Ahh! I'm being loquacious again. So please, anyoneyou don't have to tell me HOW Trapper leaves and/or HOW BJ joins, but just let me know if there were a few episodes that I've yet to see or not. Thanks a million!

Blame the producers on this one. The allowed the Frank Burns character to become childish and one-dimensional, and it failed to challenge Linville as an actor. He DID have the ability to do more with the character, but instead they opted not to change it. As a result Linville didnt want to come back.
Usually, when a character leaves, they bring in another character that is different from the one that was there. They brought in Harry Morgan whose character was different than McLean Stevensons. They did the same with David Ogden Stiers.

According to reports, he felt that after five years he'd done all he could with the character of Frank Burns. By his final season, he was also getting tired of Frank simply being the butt of the jokes. In the fifth season, when Margaret's character got engaged, they no longer acted as the team they'd been. After that,5b4 his character become more isolated and it didn't seem as much fun to see Frank constantly get tormented.
His contract expired at the end of that season, and he opted not to renew it. It sounds like if they'd changed Frank's character somewhate -tried to make him more human, more sensitive, etc, he may have stayed.