FATboy,
When calculating climb performance OEI, the AF actually allows us to scrape paint...provided the first two options listed below aren't feasible.
11-202V3 (Of course your MAJCOM or 11-MDS may restrict it further)
8.7.2.2.1 The following methods are authorized for computing engine-out climb performance on departure. Methods may not be combined. These are in priority order
8.7.2.2.1.1. Meet or exceed the published climb gradient, or 200 ft/nm (whichever is higher) for the selected departure, with one-engine inoperative, or;
8.7.2.2.1.2. Special Departure Procedure (SDP) (if available), or;
8.7.2.2.1.3. Vertically clear all obstacles along the planned departure path with one engine inoperative, or;
So if you are down to using the third option, the only acceptable technique to calculate required OEI CG is to subtract .8% (48 ft/nm) from the published CG. This is regardless of whether the published CG was calculated using the old 48 ft/nm required obstacle clearance (ROC) or the current 24% ROC. (fully detailed in 11-217V1 chpt 9)
So with a standard climb of 3.3% (200 ft/nm) your OEI climb requirement is 2.5% (152 ft/nm)