Ok, shedding, well, frankly they only shed their dead coat, they have (like most breeds) an inner (softer) and outer (sleeker/firmer) coat – they shed the undercoat once a year, and the outer twice a year – so one moult is more obvious than the other.
Clumbers do not shed as badly/heavily as a German Shepherd, Malamute, Corgi, but of course there is more undercoat than on the smooth hounds like the Beagle.
Excessive shedding is very often linked to inappropriate diet or other ill thrift/health – most times lifestyle induced. Having white coats the odd hair loss throughout the year (like we do ourselves) does leave obvious evidence in dark corners or against dark furniture – but, hey, we can see it and quickly collect the few stray hairs.