I'm mixed on this one. Perfect us generally very expensive or doesn't actually exist. Quite often I'll use this in the place of "shit or get off the pot" as the search of Perfect will delay getting anything done.
Yeah this is generally how I use it, too. I don’t think of it as thought-terminating in those cases… if anything, it’s the opposite. Dismissal in pursuit of perfection feels more thought-terminating to me, because it shuts down discussion of what can be done now, how to mitigate downside, and gradually work towards an ideal instead favoring doing nothing and waiting for some highly improbable ready-made ideal solution to present itself at some indeterminate point in the future.