Yes i understand what you say, but i believe u are taking what im saying literally and you don't see what i'm saying yet. Besides arent the threads the ones that are taking all the stress but the whole shell. U are repairing the threads to get the BB into the shell. The shell wont have any problem after is rethreaded using the durafix rod.

But if you have the bad idea of reparing an old aluminum frame that got a problem (crack) in a welding for example in the joint of the TT and the Head tube, the durafix will work and will get the thing repaired pretty good, so good that the frame will crack in another place because the new welding is stronger than any welding in the frame. Durafix works awesome to repair threads in bikes. But not for repairing cracks.

There is a guy with a marin frame with that problem right now, look at the thread, I didnt even mention the product because will be a waste, aluminum frame with a nasty crack.

U can repair aluminum frames pretty easily and at home with this product, but if you dont have where to apply the heat treatment to the frames after wards the fix will be a waste because the frame will brake again warrantied probably next to the repair.