If you may indulge me a little bit further:

i was just trying to be polite

For the record, it's not my intent to be impolite, either. I do welcome corrections to fine-tune my knowledge.

what i wrote is not the same as what you did

Apologies; what I meant to do was to contrast your 'SAT' example against your 'height' example.

your comment is clearly incorrect... for the most obvious example what if X and Y are always the same value? then saying E[X+Y|Y=y] = E[X] + y in the general case is obviously ridiculous, is it not.

I admit I was wrong, as abstrusiosity noted. (The sad part is this is not the first time I made a bad assumption about conditional expectations).

Anyhow, thank you for your input.