That's what I mean, not a general ritual, but a specific ritual against checking out at the end of session. My T and I have one, actually a few.

One's visualization oriented, one's more practical, activity oriented, and a third is a physical exercise.

So that whether or not she picks up on your dissociation, you're doing work to counter it. If it turns out you didn't need it that session, it's ok, but it's there as a safeguard.