There seems to be a great emphasis on checking nose weight for some reason and although I wouldn't condone exceeding stated limits for your outfit, of much more importance from a safety aspect is overall weight and correct loading of caravans.
Too little nose weight can have and adverse effect on caravan stability but none of the methods described to measure noseweight here or anywhere else can be guaranteed to be accurate, including bits of wood and bathroom scales which are notoriously inaccurate to start with.
My guess is that the Reich version would be the best of a bad bunch but as the Prof pointed out, noseweight is not static when a caravan is moving along a road surface, it can and does vary greatly due to the relative angles of the hitch / A frame and the towbar/ towball so the best that we can achieve is a mean average.
I have yet to discover any evidence whatsoever of a successful prosecution based on caravan noseweight so to my mind a quick lift of the hitch is as good a method as anything, at least if you can lift it the chances are that you won't exceed it by any significant amount.
Caravan weight is sometimes checked at the roadside by VOSA but they don't check noseweight. How many caravanners does anybody ever see checking their noseweight before hitching up after a break to head home?