I posted a similar thread a few months ago and gave a link to a West Marine
article from their site. I had a thur fitting completely corrode away last year and the only thing between the sea and the interior
of the boat on a 1/1/4" hole was caulking.
So after some research
I when though the boat and unbonded all the thur valves. Now the only things boanded are the fuel tank
Seems that normally is wrong with bonding the valves, but the wires need to be well maintained.
But in the end this just my opinion.