So I'm gonna make a few simple diagrams to explain this.
Pull ups
oo Now, the o's (hands) are shoulder width apart. Pulling body up.
o o If you do this, your arms will not only be pulling up, but also sideways, thus wasting energy which makes it harder.
More than shoulder width is not necessarily as big of a waste of energy as you're saying -- wide grip pulls are just putting your shoulders in a vulnerable range of motion without much benefit at all, especially since its not a "natural" position.
Push ups
olo The l is where your shoulders would be in the down position. O's are hands.
l
o o If you do that it is the same concept. You are not only pushing up, but you are pushing towards your feet, which wastes energy.
Guess you never heard of pseudo-planche pushups? Not working on the planche i take it...
Pretty much all pushup variations are useful.
Also, do pus or cus work obliques?
