thinking about other stories

I've been trying to figure out whether the lure of other stories (ie. stories by me that aren't Cost of Silver) is a distraction or a relief. I used to work on two or three stories at a time, working on one file until I ran dry or wrote myself into a corner, then saving it and pulling out another. This year it's been pretty much working on Cost of Silver, then mucking about uselessly on the internet, too tired to produce anything useful like a blog post or another story.
I wonder sometimes whether I'd have more energy for writing if I wrote other things, or whether I'd just be wasting the energy that I do have. Theoretically, if I needed a break / change, I could just work on another scene or the other storyline of CoS, which is what Scrivener allows me to do easily. So why is it so hard to buckle down and do that?

Oh, those other stories. So enticing in their open-endedness, their possibilities of plot and plot twists. Those characters I don't know yet, who might do anything. Those settings I would need to research, and research a little more. Mmmm.

Then there's my stack of unread books by other people. But let's not talk about that. I have to go and write some more now.