Originally Posted by
FLYcrash
1x9 is pretty wide. Your chain's going to be at a pretty big angle in the extreme gears in any case, so it's pointless to lose sleep over chainline.
He should still try to get the chainring as centered on the cassette as possible. I was using a 3 x 9 setup, but I had no problems using the whole cassette with my middle chainring (42 tooth on a 52/42/30). Unless he'll be riding all hills with no flats, he'll spend most of his time in the middle of the cassette anyway assuming he picks an appropriate chainring (my vote is for a 42).