Did you see this article about mechanized grape vine pruning? I'm sure there is a quality trade-off over labor costs, but the proof will be in the crop results. I note that the developer/inventor is here in San Diego, but they must go clear up to Central Valley to test it out. We still have GRAPE DAY events here, but very few vinyards. oh well.

...SNIP....With the skill and precision of Edward Scissorhands, two robotic arms connected to pruners clip vines at LangeTwins Winery on Friday morning.

Completely guided with video cameras mounted on the front and a computer, the machine knows exactly how to trim the delicate vines.

While it still is in the prototype phase, the pruner could forever change grape farming because the vines will no longer need to be pruned by hand.

Here is a link that might be useful: Mechanical grape vine pruner