don't wait for disagreement, codify it NOW before there's a problem. again, that problem is AT WORST 3 lbs with a 2% engine modifier but if this system becomes a more common practice, you could expect that delta to grow.

and as I said above, 3 lbs is enough to bump you at impound, and it's 3# higher the tGA way than the tEH way. just state the order of operations, and do that every time you add percent weight changes to other allowances.