Yes and yes

I've always done it with fish in QT and it calms them down very well. I sit at my desk in the sump room with my back to the fish and turn to look at them when I remember to. A day or 2 of 1-2 hour seatings and they are happy to see me come in the room.
I had all our fish in a holding tank by the front door for 3 months while I rebuilt our system. We only passed by them going through the front door. They became quite skittish.
When I put them back in the DT I sat with them every day for about an hour. Took about 3 days and they were back to normal.
I also did no maintenance near 'sitting' time. Just sit and hang out then leave.
Whenever I'd feed I'd walk up to the tank, gently tap on the canopy and then say 'dinner time!'