IMO there is more lag, more glitching, more text buffer delay, more rubber bullets, more lost shots, more warping, more vox loss (across multiple arenas) when TT is running.
Somebody at HTC has said before that the CPU load isn't even close to being pegged, but SOMETHING somewhere (some cog in the system) cannot handle it well.
In my opinion TT doesn't work. It's not the cesspool (although that's a factor) that kills it. It's the fact that it cannot run as smoothly, even if you choose to fly/fight in a small secluded less-populated corner of the map you still suffer.
Moving away from a single LWA was a good move, because the rest of the week these things are scarce, but on Tuesdays it was so bad I stopped playing. I'd be ready to log in, remember it's Tuesday, and boot up Half-Life 2 or something else.