Not covered:
Repairs directly attributed to:
-normal wear and tear, including cosmetics, rust, and lockup
-damage directly caused by owner's modifications, including the results of disassembling the knife [that includes stripped screws, not fitting together precisely, etc.]
-damage to the blade if not the result of manufacturing defect
Covered:
--everything else
Reasoning: The things not covered are in two camps, one being problems that are the result of the actions of the owner and are not implicit in the design or manufacturing (rust, damage to the blade, and modifications), and the other being things that will necessarily happen to the knife over time and do not negatively affect its use (cosmetics and lockup--well, lockup as long as the design allows it to move over to 100% lockup and still lock)
Also implicit in the warranty is that problems are not covered if the owner's actions caused them. To put it another way, I don't agree that there should be any ultimate deal-breakers, like many people have suggested (UDT-Seal with misuse, TTD with disassembly or using power tools on it), meaning you do something to the knife, and that causes the warranty to be voided so that any damage, even if unrelated to the reason the warranty was voided, isn't covered. If it's the owner's fault, fine; if it's not, it should be covered, regardless of the status of the overall knife. It seems crazy to me to tell people how they can use what they own--which includes (ab)use, disassembly, and means of sharpening, to give a short list--and saying any of those things voids the warranty entirely does exactly that. Of course, if they do something that harms the knife, it's their fault and should have to pay for the fix (which is why mods, messing up disassembly, and damage to the blade aren't covered), but otherwise, it should be fixed under warranty.