Hey, let's not start heading into a flame war over here, mkay?
joonveen's comment might've been a bit critical (a bit of praise for what Uzaghi got right would've been welcome) but in the end, it's all to help you improve. If you get a comment that says "The grabbing tended to make the flow of the replay suffer" then you know for next time to use less grab to leave a smoother finish. When commenting on replays, it's important not to kick the person in the face just because you didn't like what the replay contained. State that you would've preferred it to be smoother, less jerky or whatever's wrong but try to counter it with a good point so that people have something to build upon for next time.
So yeah, constructive comments ideally show the pros and cons of a replay. The bits to work on and the bits to pat yourself on the back and know you achieved something.
P.S. Would the next person who posts a replay please comment on joonveen's decap dance? I wouldn't want the replay to be buried by this post.