Hmmmm, don't be so convinced...in my miles of Penwith tromping (I live near Penzance), footpaths out there are in far the worst condition of anywhere I've ever walked on these isles! Barbed wire, collapsed stiles, being thrown off by landowners, impassable generations of gorse and nettles, no waymarking, stroppy bulls...you name it. Try planning a walk at random on the 1:25 000 sheet and I can pretty much promise you, inland on the peninsula you won't complete one without real problems...particulary central and north.
Conversely, some of the better used and more negotiable paths around there are the ones which are NOT rights of way - the ones marked as black dashes. Kenidjack moors is crisscrossed with these - cutting these will be another nail in Penwith accessibility.....