It seems like the point here is that 'normal negotiation' is flawed. If you're really planning to invest (or accept investment), you're going to be filling out

It seems like the point here is that 'normal negotiation' is flawed. If you're really planning to invest (or accept investment), you're going to be filling out a large and thorough contract fairly soon anyway. What's the harm in starting out with a mini-contract, unless you want an option to weasel out? If there are other things to consider that prevent you from doing this, then you shouldn't be verbally making those same commitments. There's still room to say "strongly interested" or whatever instead, but you shouldn't expect your place in line to be saved if others say "definitely" and follow the protocol.