Yes - I have had the experience where a Japanese SP spent the next several months apparently scanning manifests for me after I put a complimentary comment in (they anonymize them but it was obvious from the comment who I was and she remembered my name somehow). She then found me on a flight, taking me by surprise (I remember I'd been op-up'd to 1K) and put on a very effusive show of thanks (no - don't take that the wrong way - it was all very proper, but frankly I do wonder what the others in the cabin thought was going on !).