When i started in the 212, i had the same problem....
Flying the 204 or 205 normally, i have always used the graphs in the checklist to recheck the calculated weight against hoverpower..
Unfortunately, there is no such graph for the 212.....if you will find one, let me know....
We came out to write down different weights and OATīs for each ship-just to have one value to check..
But normally it is not necessary-i have spoken to some of the Bell engineers, and they told me that you just have to check your hover power-and if there is 10-15% left, you can fly....
For the OEI-question-i am used to fly single engine ships, so i donīt really care...
But i had a TRE who took this serious....so i always had to stay in the OEI limits...
Where did you fly in the army (just send me a pm...)?