I'm a little late to the party (just joined) but have been arguing / evaluating this issue lately as a trainer. (I'm a competitive BBer too). You cannot shape a muscle or work parts of it, period. The pecs SEEM like an exception, but that is a myth. (And it does really feel like you are working "upper" pecs on incline, when the upper part of the chest bunches up because of the angle.) My view has been confirmed by studies using EEG. Don't worry about upper/lower/inner/outer anything. Inclines, etc are fine, but the angle won't change the muscle contraction.
And in any case, never understood why guys were trying to shape their pecs, when didn't have much pecs to start with.