I don't think most of us are looking to rip off the dealer or DM. I think the majority of us are cautious because we don't want to come in for something completely unrelated and have the dealer either void the warranty "just because", or blame the warranty work on the mods.
For example, I'm sure a dealer would blame my lift pump problems on me having an Edge EZ... those of us that are "in the know", know that the lift pump flows the same amount of fuel regardless of engine output... Whatever the engine doesn't use, is sent back to the tank... . IMHO, you would have to be putting out the power of a dragster for the injector pump to require more fuel flow than the lift pump is supposed to flow... I'm sure I'm probably wrong, but I know my little Edge EZ doesn't exceed the lift pumps flow.
BTW, I brought my truck in to have service because my driver's door was leaking when it rained and because I had a rattle in the dash I wanted to get taken care of before my 36k warranty expired... . I took my Edge EZ out just in case...

Who knows, he may tell me that my "HUGE" power output is making the dash vibrate apart.

... not worth the risk to me... . but I can tell you this, if I had my clutch "abnormally" go out I sure as heck in good conscience wouldn't go back to the dealer and blame it on them and expect them to fix it... I would quietly give South Bend a call.