In the comments jim posts a video and some small cues to help use the correct muscles in a 'handbalancer' handstand (I say handbalancer handstand as jim has learnt from Yuval Ayalon). https://m.facebook.com/?_rdr#!/99549583218/timeline/story?ut=2&hash=7668061501363883274&wstart=0&wend=1378018799&pagefilter=1&ustart&__user=100000292016661
This and 'keep hollow' made instant improvement to my one arm handstand practice.
Anyone else have any good cues or exercises that aid realising the correct shoulder position (that are not 'buy h1')