AFAIK, the gross t/o segment 2 climb gradient requirements are
2.4% for a twin (1.6% net)
2.7% for a trijet (1.8% net)
3.0% for a quad (2.0% net)
Since these numbers are with one eng inop, I expected the quads to have a *lower* gradient requirement than twins, not the opposite. I figured that quads would have a larger "engine" error margin (3 op vs. 1 op) thus allowing for a smaller gradient error margin
A "quad" has 75% power (1/3 of it on the side with the inop engine) available with 1 engine inop, a tri has 66%, and a twin has 50%. It is VERY logical that the 1-engine-inop numbers would reflect that fact.