Yes. I'm one of those 1K passengers, sorry. I fly when work asks (mid-week, non-mid week, weekend) and I apply my RPUs to flights out of IAD. Even then I sometimes clear and sometimes don't. It's a hit or a miss even for me on an instrument. And if you're ever curious about how many 1Ks are on a flight, can't you just watch pre-boarding? For my flight today, it was around 20 people all boarding when pre-boarding was called. Add another 3 for GS and yes, that sounds about right that you're 25 down in the list being Platinum.
Being Silver Spring based, why don't you fly out of BWI? Your upgrade percentages BWI-LAX/SFO will be much better. I even got them as a Gold my first year with UA before I hit 1K status.