You'll disprove it.
It's a known phenomenon, especially in construction, where bolts and washers of different metals rust heavily, as they're exposed to the elements.
If the water touches the block (and it does) and it touches the barbs (and it does), then there will be galvanic corrosion.
Water, distilled water, additives, it doesn't matter, it still happens, but at a slower speed with the additives.
Grounding strap, no strap, it makes no difference. It's as inescapable as oxygen in the air.