tedric wrote:when the thing that kills you on your first try is not "the game is hard and sometimes you die" but "the game gives you places to go way before you're ready, and you're meant to learn you're not ready by going in there and dying" -- that's a spoiler
(this is different from all the other stuff you learn by playing, e.g. encountering new monsters, because [a] you mostly encounter them at the depth at which you're likely to be prepared for them and [b] the game gives you clear indicators of their relative threat level and interface tools to learn detailed info about their power level, spells, resists, etc. and it gives you similar information about items and spells. in fact, when a monster's deadly abilities or an item's functions are not properly documented in-game it's considered a breach of the "clarity" design goal. but the placement of branches seems to break this pattern on purpose)
otoh i bet it's pretty rare that somebody reaches Lair on their very first game and dies by immediately entering an S branch, but it's still flawed reasoning
crawl throws excessively dangerous monsters at you all the time. 'oods' are not actually rare, and many common monsters (the d:1 gnoll!) may be too tough for some characters. it is a core dcss skill to be able to recognize, 'this situation will kill me if i stay in it, and i need to flee immediately'.
branches are not fundamentally different. when you enter a new branch, you encounter new sets of monsters, and have to evaluate them accordingly. you can examine them and see, oh, all these monsters are marked 'very dangerous', they all seem to be pretty vicious compared to the stuff i've just been fighting, they're doing a lot of damage, maybe i should run away! i don't think this situation is perfect - i think we could give more information about monsters than we currently are - but the basic approach is, to me, reasonable.
it's not even a fundamental difference between new & experienced players - though of course it'll happen less often, there are times when i've entered a branch, discovered i'd overestimated my character's strength, and had to bail or die.
as long as extended exists, this mechanic is going to exist - a player entering hells, or tomb, or pan, is going to be entering a branch that's significantly harder than the one they came from. i think it's much better to introduce the concept of "harder sub-branches" earlier in the game - the earlier we get characters killed off, the less pain we inflict.