I would go with what the owners manual says.

Unhunh....  The $5.00 per hour burger flipper (if he didn't have the
costco job) that wants to charge you a fee is even slightly credible vs
the owners manual????

I don't think so.....

I have over $800 in my Jeep's tires and the owners manual says to 'only'
flip them front to back.  Tire shops say no way, you need to cross them
because tires are 'better' now than when my owners manual was made.  I
call them on their BS.  My last set of tires wore out perfectly even
right down to the wear bars and the current set of BFG Mud tires have 7
years and about 50% wear on them with perfectly even tread wear.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos:  Non members can still view!
Jan/06 http://www.imagestation.com/album/pictures.html?id=2115147590
(More Off Road album links at bottom of the view page)

Don't bother.
Remember that every time a tire is mounted/dismounted it can cause
damage, to the tire or to the rim. Then there is the balancing.
Depending on the weight types you can end up with chewed up rims.
And then you have the fact that the "Pro tire installer" (who works a
second job with the keys words being "Do you want fries with that") Who
is telling you to do something the factory says not to do.