Yes, it is better for the plant to leave the bine in place, however in my area they grow like weeds so it is no big deal to hack them down for harvest - in fact it might be better to do that to keep them in check a tiny bit. If you have a weak plant or they don't grow well in your area, it is best to leave as much of the plant as possible to let it store more energy. The galena you have for example, you should leave it alone this year for sure.