And THAT could be used as a startup retard mechanically if done right, because there is some since the weights move a bit before the springs start resisting.
Technically your base timing is where the distributor is physically with whatever amount the weights move before the springs stop them.
The problem to solve is that the weights are still at the end of that free travel when starting instead of returning all the way back to the stops, so solve that and there is your startup retard (some anyway)