You´ll probably get as many answers on this one as there is riders. Some of us over-inflate and regards it as the best way to make the bike go faster. Even att recommended pressure we sense a squishy rolling resistance (or we´re just a bit neurotic and senseless to how bumpy the ride gets!). A wider tyre should take up shocks better, even when pumped hard, but I´m not sure as I never run fat tyres. Its a bit mathematic (your weight, type of tyres&rims), the feel of the bike, type of surface, riding style and so on. I´m generally go 20 psi above recommended max pressure.