Popeye,
Here's a few pics from my lowish speed off at Croft 2 years back with bungs fitted.
Both Felix and myself have 'tested'
the thru-the-frame concept and the general concensus is to ditch the idea in favour of a sturdy clutch cover and reinforced (Kevlar tape) bodywork.
When/if the bike slide across the tarmac and then inevitably hits the curb at speed, there's only one result which is shown in my first pic here