Remember you get your brebas on the ONE year old branches, so if you prune them you will not have that early crop... best to just take a little at the tips to help it branch out, or do nothing, only remove the thinner branches that act like suckers, and leave the energy for the stronger ones that will make the best fruits. when you cut the thin ones, remember to leave at least 2 nodes...it is the growth of these 2 nodes that will fruit next year, plan on the 'year growth of this year' will fruit next year...so, when pruning, think what you want this year and next also.
In Grapes, they call this '2 node' pruning 'renewal', it is the same concept.