Yeah Batmam, you are ecorrect. The excess current is dumped to earth and you will find that the pin that corrodes, heats up and disintigrates is the earth pin. On my Ten I cut off the complete block and hard soldered a Reg / Rectifier off a Fazer (same coloured wiring). This item has about 300mm of loom potted directly into the unit. I unwound the loom of the original wiring back as far as the horn junction and connected the new unit to the loom. This gave me a faif amount of extra loom which allowed me to mount the regulator underneath the headlight. No more problems. Job done. A full explanation with pics is somewhere in this forum.
I'll try and find it.

Cheers Steve

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