Yes that should work as all you really need is a delay of each retract to start moving.

Just to confirm you would like when you flick the retract switch for one leg to start moving then after a preset delay the other starts moving?
If so then it can be done with a simple time delay circuit switching a mosfet, so long as the gear ECU dos'nt turn of the power to that leg if it senses no current.
Really what is needed here is a programmable Gear ECU