I have a Gibson SG and it too has the neck dive problem.
It affected Pete Townshend as well
Yes the SG is well known for neck dive problems, I had an SG bass once (it was famously used by Jack Bruce in Cream) and it was terrible, Leo Fender made very balanced guitars and basses so Ive never had a problem with a Fender.
Its not a massive problem on the Hofner Violin bass as its so light (hollow bodied) mine has a strap button where the neck joins the body and I find by using a fender webbing type strap it doesnt slide on my shoulder and sort of grips my shirt preventing the dive, this wouldnt work on a heavier guitar like an SG though.
I think Hofner should make him honorary chairman or something - where would they be without him?!
Ive thought this loads of times Peter, check ebay there are loads for sale (new ones) so its still a big seller, its funny theyve never made a signature model like Fender do with strats (Clapton, SRV, Jeff Beck, etc ) but then again its like every violin bass is a McCartney signature as no-one else uses it.
If you can ever get him to sign it on the picguard Barry it would be worth about $10,000