Gmaxwell earned more Merit with less posts, so if that's any indicator, I'd say yes.
But the reason why we say "more skilled" is because we have the knowledge of what they do and how they have helped bitcoin.
What about 2 hypothetical users:
User A - 800 merits, 2000 posts, engaging primarily in bitcoin technical board
User B - 1500 merits, 2000 posts, engaging everywhere else than bitcoin board
Who is more skilled?
Apparently user B is "a better poster", but is he more skilled?