I have noticed while playing on other servers with no replays enabled, that I was consistently getting more direct grenade hits with demoman than on the thg servers.
Doing a quick google search, you can find things like this.
This may not be news to anybody, but since the ammount of people who use replays is probably very small and if it really puts a heavy load on the servers, I think it would be a good idea to remove them. You also can now very easily set it up in game for it to record demos automatically of every match you play, so there's your alternative.
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