Airfoilmod
I see what youre getting at. Yes of course, you are correct. If I was doing a practice single engine climb from, say, 1000 ft I would do exactly that: stable in level flight first, and them try climbing and see what happens.
In fact I remember doing just that in days past, and even using a speed slightly higher than blueline specially if it was slightly bumpy, because I knew that if you got too slow, much bad karma would result. (To be honest, engine out on a light twin prop is just not a nice feeling, even if you can get 500ft/m on a plane which isnt heavy)
In a real failure on takeoff, I would however not do that. Chances are that there are trees rushing at you, and you must get air between you and the ground ASAP. That means blue line (or because I'm chicken, slightly faster).
Wizofoz, you are right, in fact I think NO light twin can maintain level at a higher altitude, if it is not almost empty. If you want to cross mountains at say, 16000 ft, you must plan very carefully so you know which way to turn at what point, if one engine gives, and you need to drift down at 150-200 ft/min.
regards, OORW