Why would a dealership try to avoid warranty work? Because they don't have a tech that can do Job A in X hours. Remember that all of the work is outlined in a catalog along with the service hours allocated for the work (my Indie uses the same catalog (actually it's an online subscription) to estimate their work). I could easily see a smaller dealership not wanting to deal with experience based labor items like engine swaps.

As for the article itself, this is common knowledge but it is good to sperate facts from folklore. I had my manual transmission lock out even numbered gears while tracking at VIR. Limped the car home and directly to the dealership in odd numbered gears (still had my helmet and track gear in the car). I was worried they were going to make comments about the car being tracked, exact opposite, I got thumbs up comments. However, it took them close to 3 hours to determine that they would replace the transmission under warranty. I asked why it took so long and they responded by explaining a checklist they had to go through first, a very involved checklist. Since my car was clean they didn't even have to 'ask' PCNA (though they did notify them). I almost installed a Numeric Shifter earlier and asked what would had happened if I had, they said that this would have put me into a gray area that would require correspondence with PCNA and 'if' the warranty work were approved it would take weeks to get that approval.

Lesson to be learned - don't modify anything you aren't willing to pay for repairing yourself... until your CPO expires

I think it’s interesting to see a look at how detailed a manufacturer will get to instruct its technicians about how to check for signs of mods and what to do about it. We all know that those documents exist, but always good to understand exactly what they are saying. And how they go through the decision making process. iE an I take doesn’t automatically void your warranty.