My feeling is it was a compensation for the fact that the same pulley also drives the blade disc off a twist belt. A neighbour tells me he can recall when all quarter twist drives on bore heads always had the engines mounted on a slight angle.
I've looked into link belts and this newer type seems to be the most commonly available today. This is a great video which shows how much vibration is reduced on a bench saw by using these belts. But I wonder if this belt would spin free once the lever is moved to disengaged position? Or if it would just fly off?
