I think they meant that you will not see localized growth in that area due to the injection. W/ something like Test Suspension, people have noticed localized growth from injections.
With the long esters, you don't need to inject in the bi's tri's and delts, because you really only need your thighs or glutes. I, personly, like stay away from upper-body injections if possible (w/ long esters), cause I wouldn't want to be sore from the needle during my workout. A fast-acting juice, that requires EOD or ED injections, would require the extra injection locations (bi/tri/delt).