I'm with you, friend. If I'm working, I prefer to just work until it's done or I feel I need a break. For me, starting a job, it takes a couple hours to define the problem, a couple to investigate and prioritise tasks, then to start looking into solutions, and suddenly it's time to stop. Then there's all the time commuting, taking breaks, etc.

I prefer to just get in, get in the zone, knock out a slab of work and get a job done. It takes a few extra hours on a work day, so be it, it was going to be a work day anyway. By doing that, it gives me a day off? Yes please.