First of all I would like to apologise for my abscence from the BB. I have been rather busy. Enough said.
WRT CAT A performance, the single engine performance you refer to in JAR/FAA/CARS are really a Class 1 limitation wrt take off and landing. What you refer to is what the manufacturer provides in the form of CAT A or CAT B Ops.
Simply stated, CAT A performance for most manufacturers guarantees, after CDP, the A/C can climb at 100 FPM to min sector with the gear down (most unfavourable C of G) then continue at 150 fpm (most unfavourable C of G) to MEA in an OEI condition. This will vary of course between manufacturers.
Hope this helps.
OffshoreIgor