This.

All that other stuff is a waste of time and makes merit sending too complicated. It doesn't matter what the recipient will or will not do with the merits/smerits. The purpose of the merit system is to award posts, not users.

The only thing that I occasionally check for is plagiarism - if I suspect that the user sounds unusually eloquent. But I'm sure I've merited some plagiarised posts over the years. Shit happens.