The idea is to define a minimum time that allows for discussion and community interaction before moving to an on-chain governance proposal on Zeitgeist. This is an informal measure and not strictly enforced but that should leave enough leeway between a discussion being created and some entity starting a governance proposal.
Our proposed time for is 3 days allowed for discussion. Which could be increased if deemed necessary or when Governance 2 is enacted on Zeitgeist.
It makes sense, 3 days was just an example borrowed from the Cosmos ecosystem where the minimum amount is 3 days. Though, in reality there is an unwritten etiquette to discuss for at least a week or two. Then, would it make sense an off-chain vote with these three values?
Zeitgeist generally encourages discussing proposals on this platform before launching them, as stated in the governance announcement post. It is also highly encouraged to use https://voting.opensquare.io/space/zeitgeist to create a token holder poll on an idea before launching it. Token holders can vote off-chain with their available token balance there to reflect their opinion on the proposal itself or different options of a proposal. Such polls also provide means to discuss the proposed changes. Creating a dedicated discussion post on this forum before opening the poll is also suggested, because it might improve the proposal itself and the available options before setting those up for a poll.
I wonder, what is the reason behind setting a time limit? To me it makes sense to give the proposer the freedom to decide when consensus was met off-chain and a proposal should be created or discarded and when enough time has passed without reaching consensus, which should lead to an on-chain proposal as well.
In any case, token holders can provide backing to on-chain proposals to assign more weight to those proposals. The proposal with the highest backing will always be tabled as a referendum first.