There is a difference between "can" and "should". The chainline that has the least friction, and produces the least wear is a straight chainline. The notion that someone is going to be using every cog on their cassette from the middle chain ring might help sell replacement cassettes, but is not the best way to ride a bike.

Most of the problems with "modern" drivetrains are the result of trying to provide a "gear" for any possible situation. I saw a gear chart for a "Joe Average" sort of bike that had a range from 30 gear inches to 120 gear inches. Maybe, someday, somewhere, "Joe" was gonna need those gears. But, on a given day, he was more likely to be riding in a range of about 50 inches to 80 inches.

Let's look at "real life". Eddie Merckx set the "one hour" speed record using a 97 inch gear. The maximum gear allowed in the UK for a top "junior", age 15, in supervised racing is a 76. When training, Sean Kelly used a 67 inch gear. When Greg LeMond was 15, the "Junior" race rules limited him to a maximum of a 52 x 15. As a Pro, he rarely used anything higher than a 53 x 14 maximum.

So, why in 2005, are bikes are being sold to schoolteachers, plumbers, and shoe salesmen with 53 x11 set-ups? Why do some bikes have four gear combinations between 95 inches and 130 inches? This may be good marketing - "Get 30 speeds - including speeds the Pros of the '80's never knew existed !!", but it ignores human biology. The average schoolteacher of 2005 is not stronger than Eddie Merckx in his prime.

Most riders would be more efficient if they learned to spin at high rates, between 90 RPM and 100 RPM. If a road bike (not a touring bike) is geared from about 40 inches to 95 inches, a rider can easily access any gear between 40 iches and 95 inches with just 10 well-aligned gears.

A 2 x 8 system can easily produce 10 distinctly different gear combinations that have a straight chainline. And, if those 10 combinations are carefully matched to the needs of the individual rider, they are all that he will need in the course of any single day of riding. (For "sprints" a different cassette would be used, for loaded touring in the mountains, a different cassette would be used).

Mr. Shimano admitted in a recent interview that the gearing on a average road bike has no relationship to the acual needs of the riders. However, he says people who buly a road bike insist on buying a bike that is EXACTLY identical to what they think Pros ride. So, Mr. Shimano thinks "silly" gearing sells bikes.