Pruning soft fruit before I even plant them?!

[nickdub]

What festooning does is affects the way buds develop on branches. Its a rather complicated subject, but the main result is that you get more and more densely packed fruit buds on branches that are festooned than you would if those branches were left to develop without bending and they form sooner.

Of course in the end the total crop a tree can bear is a function of the overall size of the tree - so if you stunt your tree in any way, it can never reach the maximum weight of crop it could have achieved if you hadn't intervened.