I believe I have had better survival rates when I planted fruit trees in the fall.
If they are bareroot, I prune off one third or so of the wood to rebalance the root-to-shoot ratio, since some of the root gets lost when they get dug up. If they have been grown in watered pots for the season and I don't plan to water them once they are in the ground, I also prune off one third or so, because the roots won't be able to scavenge enough water out of my soil to support so much top growth.
As far as timing of when I prune, if I plan to offer the prunings on the scion trade thread, I wait until late winter to prune them. If I don't plan to offer the scions for trade, I prune the trees when I plant them.
If they are bareroot, I prune off one third or so of the wood to rebalance the root-to-shoot ratio, since some of the root gets lost when they get dug up. If they have been grown in watered pots for the season and I don't plan to water them once they are in the ground, I also prune off one third or so, because the roots won't be able to scavenge enough water out of my soil to support so much top growth.
As far as timing of when I prune, if I plan to offer the prunings on the scion trade thread, I wait until late winter to prune them. If I don't plan to offer the scions for trade, I prune the trees when I plant them.