I certainly agree that the remote hover trim is difficult for the winch op to handle, they already have a high workload. The RHT device on the S-76 is not the easiest to use.
On the SAR unit I used to fly for, we sometimes let the winch operators practice RHT wet drums at their request for training. Usually, once they had done enough (or when we got short of fuel
!) we used to take back control to pick up the drum using their patter! We learned a lot of new swear words during this training..... enough said!