3 minutes isn't necessarily the point. Not getting tired while hanging with a group is nice, though. Not getting flats is nice. If one has a good LD frame, tires and pressures don't make or break anything. I've ridden 23c @ 140 lbs. on many a long ride or brevet with complete comfort and not a little speed. Saying "my tires are better than your tires" is pretty funny though. On what bike in which season in what weather on which roads with what expectations with which riders? But I hope the sixer meant this thread to be entertaining rather than a flame-fest. Entertainment is what's being offered, that's for sure.
I would say that if I added 3 minutes in 20-25 miles I'd be so far off the back of the group of friends that I hang with now - and going a little harder is not an option. But everyone has a different situation, different goals. Ride what makes you happy, if you can find it, happiness that is. Tire technology keeps changing and getting better. My favorite tires last year are not my favorite tires this year. It's a constant search.