add a little text clarifying the behavior of 'select'
add a little text clarifying the behavior of 'select'

R=gri
DELTA=18  (8 added, 2 deleted, 8 changed)
OCL=16356
CL=16356

tav/go,tav/go,tav/go,tav/go,tav/go,tav/go,tav/go