I'm currently in a discussion in rec.arts.sf.written about whether it's important to say "painting the lily" (the actual Shakespeare quote) rather than the more common (in both senses) "gilding the lily".
Do you care whether people use the original quote? Have you ever been around people who did?
A lot of time was spent on the sternum--just paying attention to the spine means that the front of the body isn't adequately involved.
In particular, the body needs to bend a little leading into moves and then straighten (without overdoing it--not arching the lower back) at the culmination of moves.
This is difficult, but it helps tremoundously.
We also worked on my not pushing/overextending when I do push hands--it's a pervasive problem. I'm not having as much fun shoving as I used to, but that just clarifies how compulsive it is.