All scandium frames have a shelf life so enjoy them while they last lads…
That story about hitting the brakes is ridiculous. This isn't Top Gun ("I'll hit the brakes, he'll fly right by"). How someone could be that much of an ass, I cannot understand.
Around here, we see a lot of the same people on our lunch rides every day, usually going in the other direction or coming up behind them because the guys I ride with are quick and we usually number 3 or 4 whereas everyone else is in 1's and 2's. Sometimes after we pass someone they jump on the back and usually stay there so we don't mind - so it's a bit different because our paceline is informal unless we're trying to clock a 40+ avg around the lake. Anyway, whenever they peel off they always yell "grazie" and it's all good. If it's someone we know we sometimes switch to 2x2 and chat for a while. Hell, there's lots of pros training around here all the time (Oscar Freire and Cadel Evans live here and many others) and they're usually happy to have someone else to do a few k's with. Anyway, when you're doing almost the same speed it's tough not to join up with someone. What a difference in attitudes, though.
If it's a training paceline you shouldn't jump in, that's fair. But I would have kicked that guy's ass in a big way - what a prick. Committing a faux pas is nowhere near as bad as deliberately taking someone out. A few quick words will sort someone out whereas taking him down is actually assault.