Well yes I don't think even pretty bold pilots would do a DIY letdown through OVC004.
Over the sea, perhaps, but that only gets you into a runway which is right on the coast.
It's a question of degree. Many, myself included, would be happy to do it through OVC010 but one has to study the chart and also Ordnance Survey maps of the area very carefully beforehand.
There is no suggestion, I hope, of doing this with an ADF. That's a great way to get killed. A GPS plus VOR/DME would be my minimum equipment i.e. two unconnected position fixing methods.
Incidentally, ADF is affected not only by coasts but also by high terrain close to the aerial. At Shoreham you get a huge error, 30 degrees easily, on the 20 approach even if approaching more or less perpendicular to the coast (when any coastal effect should be symmetrical).
Sometimes NDB approaches can't be avoided. Like Berlin Tempelhof (EDDI) right now - ILS inoperative, the runway with VOR approaches is closed, so all you have is NDB/DME. I can just imagine somebody going in there IFR/airways and expecting for the customary radar vectored ILS
And I bet more than 50% of professional (e.g. bizjet) pilots would have made that mistake.