I have been on Match for a couple of months now.
I think you've got it right. I'm in the "don't ask, don't tell" camp. It's not lying, it's just more graceful. I think it's perfectly acceptable early on to just say you have other plans. I once met a very boring man for a lunch date from OLD, who at the end of a humorless meal murmured something about nice to meet you, but I have some other women I need to meet. I mean, why tell me that? I didn't care in this case because I didn't want to see him either.
Then there was the man I never met because for one, he felt the need to tell me about a woman he met from OLD and dated for a year who had a perfect body. OK, he was being honest, but geez.