It is entirely possible. I've done similar before and have LHR-ORD-SAT-DEN-PHL-DEN-ORD-SAT-IAD-LHR coming up in a week or so for about GBP330, based on the PHL W fare. That's about 16K miles for around 3cpm.

The challenge is to fit as much travelling as poss into each day so you don't spend too much on hotels, whilst reducing the risk of mess ups. You can obsess about gaming the system and maximising miles, but you have to stay sane too.

You shouldn't have too much trouble finding B inventory, but IIRC there's a 16 segment limit on e-tkts.

I absolutely recommend paying out for KVS and/or Expertflyer. I just take the completed itinerary to my tame TA for booking. It prices up & tickets no problem in Galileo. I couldn't face doing that thru the UA ICC

Let me know what you decide.