>hey need to be able to have 5 months where they can clear the calendars and just work on that

Otherwise known as "having a job"

Yeah. Having a job seems like it could keep you from regularly being able to stop everything for 5 months of high paid work. Maybe the money is enough from the few months that they're fine with it (and maybe it's easy for them to get a new job after or go back somewhere they've worked before). I'm genuinely curious. It seems like a lot to make for 5 months, but what do their earnings look like over a 5 or 10 year period?

I suppose its actually spread out over a long period of time