The great 'Support' mystery in singing seems to have baffled both  the professional and amateur singer for ever! Pavarotti talked about a push out, going to the toilet feeling when singing, yet other great singers advocate a gentle 'pull in'. It seems to me that both are right depending on the singer. From my own personal experience, I like to thing of support more as a high level of excited energy, which seems to create the right environment in the body for the good support.