Are EI business class fares typically much lower than the competition?

I am seeing some very attractive pricing on D fares from US->DUB this fall, and I am wondering if those prices will hold on for awhile. If these price levels (~$3000) are consistent, it could be a very attractive option for me to use for business trips, since my company technically allows biz fares but also encourages us to carefully manage our spend. Right now my method has been using GPUs on UA, which is of course hit or miss.

Also, is it possible to earn UA miles on EI ticketed flights in biz, or must the flight be ticketed by UA as a codeshare in order to earn in MP?