Yeah, that’s not how my company operates. I’m maintaining my majority share by splitting only. The VCs can go along, or they can hope their next investment is the unicorn.
Reinvesting is a minority, edge case. I can't think of a single VC company in the Bay area that can have founders reinvest shares and not cause issues raising.
I'd expect "reinvest" to mean "supply more capital to obtain more shares" in an attempt to maintain ownership percentage. The founder would have to already be rather wealthy, or be savvy enough to negotiate some other way to maintain their ownership.