Yup, T1/2-T5 in ORD is a bore. But UA to BD at IAD is relatively simple - one of the few nice points about IAD.
If anyone is doing LGA-IAD-LHR, try the solitary LGA-IAD flight that is operated by a 757. Usually light loads, reasonable service, E-upgrades to F if you've got an MP account, it doesn't seem to be hit by the same ridiculous ATC restrictions and delays that blight the CRJs and it arrives on the stand next to the LHR departure.