The term is "riding the clutch" It was an often critisied mistake done by standard drivers learning how to drive. Say goodbye to at least half the clutch's life
My Ford/NH 4610 II has the 8-spd manual transmission that is synchronized. The 3910 and 4610 are close on a lot of things so it may be synchronized. I shift mine on the (slow) fly a lot with no grinding. I have to slip the clutch some when loading the bucket with dirt from a pile.