Glad you enjoyed your holiday on the Shroppie. No he wasn't pulling your leg! Leaves are a particular problem to boats on the Shroppie this time of year as they stick to the propeller and reduce its effectiveness. Merely changing the rotation of the propeller throws them off. Something the boatmen did called a "quick chuck back". Leaves collect in the narrows of bridges and it is best to chuck back once you have gone through a bridge. You don't need to increase the revs, just engaging reverse and going forward again is enough. It is also advisable to slow down and even clutch out through a bridge to allow the water to get round the boat and to reduce the chance of picking up underwater debris.