As I say it's just a curiosity, but how did you get to that comment? Diving through all the posts? I doubt if there is any way to find poorly merited quality posts among someone's post history in a quick way.
Those merits that you received as a bump to 1000 made the two threads show up near the top in your recent merit history:
https://bitcointalk.org/index.php?action=merit;u=2836461If Welsh was looking for good posts I'd say that would have been a good place to start instead of going through the entire post history.