don't you have engine out performance sufficient to make the minimum climb out gradient on the published SID? I was under the impression that the big jets would generally be able to make the minimums and not have to rely on special company procedures.
On the contrary, twins, especially heavy ones, can be gutless, and making 3.3% (or 4% to 600ft) at 25deg AOB can limit your takeoff weight. "Down the Valley" could drastically improve your uplift.