I think its more down to the changing fuel chemistry in the last 20 years, especially the ethanol introduction.
One thing that confuses me is the reccomendations for these epoxy floats, I had a shadow wwhich had fibrelam tanks held together with epoxy (Araldite), when Ethanol started to be introduced the tank started falling apart at the internal epoxy joints...I guess this epoxy must be very different?, I'd wait a bit before rushing to this new 'solution'