Tire rotation, front<->back vs. cross to the drive-wheel

Assuming you're doing a four wheel rotation not involving the spare tire and the car uses non directional tires, it is possible to do a simple front to back rotation or cross to the drive wheel pattern.

What are the pros and cons of each method? I personally like the cross method because it will prevent wear from accumulating on one side. There is also the X pattern (LF <->RR, RF<->LR). How does this differ in outcome compared to cross to the drive wheel?

I keep them on one side because I've seen alot of vibrations pick up from turning a tire the opposite direction that it used to travel.

Modern steel belted tyres develop a pattern in the steel belts that is relative to the direction they are turning.

If you rotate them accross an axle you change the direction they turn in, which means the steel belts have to realign themselvs.
Its basicly a quick and easy way to destroy a tyre from the inside out.

You should always rotate tyres front to back and back to front only.

I have always followed my owners manual. Some said front rear, and some said across, but I never had a problem. I suppose you could check with the tire manufacture if unsure.

I ask the guys at the tire shop. They say front to rear. Many times I let them do it since it is free.

My uncle (a tire rack guy) indicated that if you follow manufacturers recommendations for intervals, the steel belt "memory" doesn't really occur. At least not enough to notice or do damage. If you are like most people and rotate them every once in a while, they may have vibration or belt separation issues if you reverse their rotation. He also said, however, there is very little harm in just going front to rear. He has noticed some tires being particularly sensitive to cupping, and on those types he recommends reversing their rotation at manufacturer's intervals. In my case, I got tires that cup easily and are unidirectional. I drive them until the fronts start to cup, then I rotate them to the back and lay some tire smoke to "even them up" as I call it. Optimal or recommended? Heck no, but fun. And those tires only last about 12k anyway.