This doesn't make sense to me. Fundamentally, you either have a signed legal contract, or you 'just' have a verbal agreement aka handshake deal. The problem that this supposedly solves, is that verbal agreements are non binding and leave wiggle room. If you cant trust the other party, the only recourse is the full legal contract. If you can trust the party then the handshake and the intention is enough. Further more…
Especially with startups with so many newly minted noobies coming on board every day who don't have any history or business knowledge they will soon might accept that this is the way "business has always been done".