Skidding will rip the crap out of a tyre given the chance, I run my pressures at around 100-110 and I'm ~175lbs, nothing spectacular. I ripped through my first back tyre in around 500 miles, which I thought was fast (great tyre just not great for skidding - I still have the matching front tyre running... 6550 miles and still going strong.)
25 miles is.... real quick - were you skidding the hell out of it down hills all day?