Cleanworks
Moderator
I find with a 2 man crew, it's better to single wand. One guy prespraying, crbing, pulling hose, moving and block and tabbing furniture, etc, the wand never stops. There is always an exception to the rule however. Doing a job with upholstery and carpets, it can be better to split that. On a lot of large commercial jobs, it's better to have 2 trucks. Set up at different ends of the building, so you're not in each others way. If you have enough staff, I can see dual wanding being effective.4 or 5 rooms with a 2 person team easily in an hour without hurrying. It's a carefully practiced team effort that keeps the wand moving smoothly.
The 870 can dual, but usually only on big projects or the largest restaurants etc.
The WM dual wands because it has entirely independent blowers and waste tanks. Still more efficient single wanding.
The 405s were once advertised as dual capable, but that's a stretch with a single 47 blower. I only do that on big upholstery jobs.
Anyone "dual wanding" from a single 45 has lower expectations.