Are stances very robust or very fragile?

Question

A follow-up for this question, because the answers were not clear.
(with Remaster we can definetely spend an action to end a stance, but I find the cost too high)

Mountain Stance states:

The only Strikes you can make are falling stone unarmed attacks

There are two ways to read this:

• The stance is fragile, if you try to use any other strike, the stance ends
• The stance is robust, you cannot even try other types of strikes

Is there any official guidance which it is? If not, what would a native speaker think?

Answer 1

By your definitions, Stances are 'robust'

The text of the Stance trait is:

A stance is a general combat strategy that you enter by using an action with the stance trait, and you remain in for some time. A stance lasts until you get knocked out, until its requirements (if any) are violated, until the encounter ends, or until you use a stance action again, whichever comes first. After you take an action with the stance trait, you can’t take another one for 1 round. You can enter or be in a stance only in encounter mode. You can Dismiss a stance.

The restriction on Strike types is not a requirement. Requirements are listed at the top of a stance. EX:

Disarming Stance
[one-action] Feat 6
[Fighter] [Stance]
Source Player Core pg. 145 2.0
Archetype Duelist*
Prerequisites trained in Athletics
Requirements You are wielding a single one-handed melee weapon and hold nothing else in your hands

Therefore, (trying) to make a non-Stance Strike does not qualify for ending the Stance, and is simply disallowed.

The cases where a Stance ends are:

• You become Unconscious
• You no longer meet the Requirements (e.g. weapon/armor usage, on the ground, etc)
• You use another Stance action
• You use an action to Dismiss the stance
• The encounter ends