We all know the UG are getting difficult (impossible sometimes) - but I wonder what strategies people use to select a seat with hopes of getting an empty middle seat - or maybe even an entire row?

I have a few upcoming segments - and unlike to get upgraded with CPU (who knows anymore) and probably not worth the miles or points (although the lay flat 757 from LAX-DEN sounds interesting, but less than 3 hours - I can rough it)..... but so far the loads (which I know are hard to predict) suggest a bunch of empty seats and rows.

In general, I tend to pick an empty row - I prefer a window - not towards the front of a series of empty rows and not towards the back as people might pick closer to the front and move back in filling the seats - and unclear how UA selects middle rows, etc when filling up stand-by?

sometimes, an entire row is better than a 737-F?