Yasso 800s

I just got back from running Yasso 800s. I ran 7 at 3:30.
The whole idea really appeals to me, especially because it promises a way to predict your marathon time without running anywhere near the full 26.2 miles.
It shouldn't take me long to get from 7 intervals to the full 10 - the amount required to do the Yasso marathon prediction.
My goal was (and probably still should be) 4 hours. But 3:30? If you are a 46 year old male marathoner, you already know what I'm thinking.
OK, I know, it's my first marathon and I'm getting way ahead of myself. My goal should be just to finish and have fun.
And that's what my goal is.
Finish and have fun.
Preferably under 4 hours.
Because it would be more fun that way.
But that's it. I'm not even thinking about you-know-what.

But just for fun, maybe I'll keep working on those 800s.