Actually, there are several formulas that dispell the idea of similar contact patch area of wide vs not wide. One of these can be found in The Automotive Chassis: Engineering principles, 2nd edition. You can find one of the formulas on BND TechSource website.
Your contact area is greater on your 195's than your 275's.
Kinda confusing, huh? Of course, I'm very easily confused. Comes with old age!
What pressure are you running cold in your Hoosiers?