see:-http://www.bushcraftuk.com/community/showthread.php?t=11878&highlight=dubbing
Many years ago it used to be advertised on the Waxoil tins ( the stuff for spraying on north sea oil rigs and under cars ) that it was excellent on leather harness, so I always give my new boots a coat the idea being if you warm it, i.e. in a jar in a pan of hot water it really penetrates the stitching. It's great for wax cotton jackets and trousers as well.I've used it on dozens of re-proofs and costs less a gallon than say a small tin of nickwax.I usually wear the coat and then get the wife to paint it all over with a paint brush then rub it in with a piece of scrap towel,works a treat
cheers Danny