Fiemme said:
A good quality frame builder will eliminate defects during the manufacturing process if they follow good frame building practices.
Well, this is where we differ then. Welding is not exact. I know the beads are pretty, but maybe the rig is running a little hot, wire speed a little too slow. There's a million little things that can and do go wrong when working with some of these fragile alloys. And there's your cracked frame that's due to workmanship....
Fiemme said:
Whether it be Steel, Titanium, Aluminium or Carbon. I personally do not believe in the notion of a lifetime warranty. Nothing is perfect and nothing will last for ever. To prove a frame broke by a manufacturing defect or whether that same breakage was cause by general fatigue is almost impossible.
Try taking a 20 year old Trek back for a warranty repair. I don't like your chances.
Much of this gets down to the shop's practices on servicing older customers if they've been around that long. Some builders will do you a favor on a 20 year old frame set that's failed. It just depends on the circumstances. If you can be flexible, the few I've dealt with are happy to deal. Some clearly won't/don't with a limited warranty.
Using Trek as an example is an apples and oranges comparison in this context.