But then that puts you into conflict with the Luton Downwind traffic which you are trying to get to 5000ft at a sensible place, not to mention that heading putting you directly underneath the BNN hold restricting your climb. Also puts you directly in conflict with Luton OLNEY deps which may have to be positioned to the East of you depending on where the LL traffic is going. Not to mention 020 off BUR means the cross is later for City and Stansted traffic again restricting your climb. Basically by going 020 off BUR, it will restrict the flexability for NW deps which is required to make the sector work.