On Sat, 29 Jul 2017 03:45:13 +0000 (UTC), Roy Tremblay
wrote:

actually wrote:

The only way to have matching tires front and rear theough the life
of the tires id ROTATE - front to rear.

Both the H and X pattern result in matching tires front and rear.
The alternating X H puts any one tire on all four corners in a year.
The two tires on any one axle always stay together as a set.

I had always assumed RWD and all four tires the same model & size.

Tire Rack says there are 2 traditional RWD rotation patterns
Rearward Cross & X-Pattern
And 2 traditional FWD rotation patterns
Forward Cross & X-Pattern
And 2 traditional performance patterns for special cases
Front-to-Rear & Side-to-Side
https://www.tirerack.com/tires/tiret....jsp?techid=43
http://www.tirereview.com/back-to-ba...vehicle-tires/

The alternating X & H pattern I devised puts each tire on each corner in a
year without compromising the axle pairing.

The disadvantage is that the direction is reversed.

If reversing non-directional radials causes the belts to separate, then
that's the major disadvantage but I can't find anything conclusively
reliable that says belts will separate merely by changing the direction for
non-directional tires.
I'm not saying they WILL separate - but you are increasing the
chance. Look at how a steel belted radial tire is built, then envision
how the belt works into the rubber carcass and takes a "set".
Now, reverse the rotation, and see what the steel belt tries to do. It
tries to "take a set" the other way. In doing so, IF IT SUCCEEDS, the
belt will get loose in the carcass, where it will cause heat buildup
as well as weaken the bond between the belt and the carcass rubber.
This is particularly dangerous when the rubber hardens a bit with age.
Some tires harden more than others - so some are more of a problem
than others.
Even without the rubber getting hard, having the steel belt shift
inside the rubber carcass is never good.If the bond between the rubber
and steel is compromized, the tire comes apart.

Running a tire with too low pressure, or significantly overloaded,
causes the same problem with the bond between the rubber and the
steel.

On a TOP QUALITY tire you MAY get away with it, but with so many even
American branded tires being thrown together offshore in places like
China, Singapore, Thailand, Viet Nam etc,do you really want to find
out the hard way???