Nice one James, good info, yeah I'd heard something about this before.https://www.soapworksltd.co.uk/soapworks-story single handedly destroyed nearly all British hard shaving soaps... They'd never made a shaving soap before and obviously didn't invest much time in finding out what's involved as they ended up producing what is essentially bath soap for everyone (apart from D.R Harris.) IIRC Floris & ToBS were the first to realise and reformulated sharpish, followed by Penhaligon's and more recently Crabtree & Evelyn... GFT and T&H still deny there is any problem to this day
These dud soaps can be easily identified by the first ingredient, if Sodium Palmate then its rubbish, if Potassium Palmate then its good
Also it seems like Penhaligons have stopped doing soaps according to one of their staff..(I emailed a while ago and they told me they're only now available in their in their outlets while stocks last) shame really as the BB hard soap I have performs excellently, though it is an old puck. TOBS soap is decent and D R Harris as you mentioned..the rest (Trumpers, T&H , Floris et al) I will steer clear of!