I work with Wor Lass, and it takes little planning and practise to work efficiently.
For example, we pull up at a job, I unload the hose reels, she takes her pole, grabs her hose and off she trundles to the place where she's going to work, I then grab my pole and hose and go to where I'm going to work.
Ideally, I finish five minutes before her, pack up my hose and pole, go and collect, and when I've finished that she's finished, and reeled in her hose.
But in practise, what often happens is that I collect and she's still working. There isn't enough work left to warrant me pulling my hose and pole to what's left, so I'll either take over and finish for her, or I'll have a coffee and hide around the back of the van while she's finishing off. So one of us will be hanging around at times.
I think for two people to do the double amount of work as one, it takes a bit of teamwork and practise, and it is possible, but more than likely no, it'll be less than double.