Ok, I understand. Surely, "unwind" communicates unroll, relax, loosen up etc. In the Italian version, we had a flatter translation, which I could re-translate in "Describe how the fiction provides you with an opportunity to recover".

That generic "recover", coupled with the apparently very short-timed actions (take a pill, turn up the volume, punch the wall...) suggests the idea that you simply need a cool cutaway/flash-cut of just a couple of seconds, in which your hero, cornered, takes a painkiller and shouts a one-liner before running back into the enemies; or the chased driver puts his favorite song on the car-audio system, turns up the volume, before attempting a dangerous stunt etc.

I think that it's very easy to misunderstand the idea behind those rules (also, they are so compressed... 😁). The game can heavily change its whole tone based on the interpretation of that single phrase.

Clearly, the previous "Once per run" gives a very precise instruction on how much Stress you can hope to recover in the whole mission.

On the contrary, removing the limit and implying that you only need a quick flash-cut action make it seems as though the heroes have an almost infinite quantity of Stress at their disposal.

Apparently, though, the "standard" behaviour seems to be related less to a hard limit and more to the availability of a downtime scene (either because there's time for it, or because the party actively works to create an opportunity for it).