Players need to be prepared for mousetraps. It's going to happen.
Now, I don't bring my point up without support. Yes, players usually don't miss a stationary target, but time by time they make a mistake, maybe 0.1% of the time.
So that is not a big problem.
Let's also ignore the fact that Starward Rogue's rule(saw it somewhere else in this forum too, somewhere...) to be clearable with just the main weapon of any mech, at base damage. Breaking this breaks player expectation, because it is like breaking a premise in a chain of logic.
Take one step back, assuming that rule doesn't exist, there is no
indication that such hard requirements are needed. Boss rooms are magenta, Minibosses are purple, Major Item rooms are green, normal rooms are cyan, etc. You don't surprise yourself to see a boss unprepared -- you
know when to enter a boss room. Unless a new color is assigned
specifically to rooms that
hard requires consumables, players will be confused.
So my point: unless that design rule is non-existant, you should
never break it. Because it instantly triggers slippery slope, or an impression of slippery slope, among players. You break it once, there will be another, and it goes spiral.
Or maybe I can't make this argument because you are changing your rules anyways. Yeah, that would break my premise.
Last note here: as for players missing missiles against stationary blocks. If people aim with analog stick at some distance away(maybe just lazily saving travel time), they MISS. No matter what you say, I sometimes do accidentally release my stick and
puff, missile to the left.