The only "'mercun" trousers I've ever seen with only one back pocket are those in the "youth market" and often had another obscene modification - elastic waistbands with no belt loops. Being of an age to wear "big boy" clothing before mass merchandising decided that only teen agers have any money, I may have missed something.

Amos complains about the wallet in the back pocket throwing his back out. He problably has the problem cited by the CEO of American Airlines in a speech at Boeing a few years back, when he explained that he'd finally figured out that that "bump" on the front end of 747s was so the pilots wouldn't bang their heads when they sat down on their wallets.

It's most common to have a pocket on each side in front, and two on the rump. Traditionally the left rear pocket has a button, since it seems to be common for people to carry their money (obsolete term - substitute credit/debit cards) there.

Another "neat trick" is the left back pocket without a button, but with the opening stitched narrower than the main width of the pocket so that the contents have to be carefully "centered" and lifted straight out to prevent hooking on the top stitching. This can be so effective that it may be easiest to drop your pants so you can get to the pocket with both hands in order to extract an overstuffed wallet. (Makes it easy to get "beat to the check" when it comes time to "fumble for the tab," so this style appears most often on "dressy" trousers suitable for business wear.)

Although I've used the term "wallet" in deference to prior use in the thread, if it folds up to fit in a rear pocket in US usage it would be called a "billfold." The wallet name is applied in my area only to those long things that require you to wear a "monkey suit" to have an inside jacket pocket to carry them in or to the monster things with zippers attached by massive chains to the belts of truck drivers and wannabe bikers.

Of course, according to my understanding of traditional lore, this is all academic here. Why would a musician have any need for a way to carry money?

John