SpeedofLite 

TenGrainBread 

Funny how sure of themselves the judges sound. Their opinion about where to connect the seatstays to the main triangle sounds reasonable but is somewhat outdated. In theory it makes sense to attach them at the thick seat lug but I think in practice the forces at play are not strong enough to make doing so absolutely necessary, especially on a road bike. It also ignores the fact that there is no seatlug on many fillet-brazed frames and yet those frames hold up fine with seatstays attached directly to seattube.

It sort of makes sense as commercial framebuilders tend to overbuild their bikes for customers.

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Doug Fattic 

If I was a judge I would be put demerits on a frame that attaches seat stays directly to the top of a single butted seat tube. Most standard seat tubes have a wall thickness at the bottom bracket shell of 0.9mm. At the top, it is a very thin 0.6mm. Fillet brazing the seat stays onto that very thin tubing would have high odds that it might eventually crack. And there is also a good chance the seat tube will bulge out with the necessary brazing heat. A commercial framebuilder would not want to take any chance of the seat stays cracking or bulging that would hurt both their reputation and pocketbook.

There are several ways to solve the problem including putting another piece of tube on the seat tube where the seat stays will attach. Raleigh did that with their fast back frames. Another option is to use outside butted seat tubes (if it a fillet brazed frame). The True Temper ones were 1.3mm thick at the top. This makes it look like it isn't reinforced unless you look close. I wouldn't take this chance but using a double butted .9/.6/.9 tube (requiring a 26.6 seat post) would lessen the chance the joint would eventually break.