I've just finished my first playthrough and was surprised to note that when I prepared for the penultimate mission, the option to spend intel for various special effects was available - increase the squad size, better concealment, etc. I never noticed this on any other mission, but it seems a neat concept and it struck me as unlikely that there would only be one mission in the entire game where this is possible.
I am thinking that maybe the options were never presented the rest of the time because I tended to be running at very low intel, spending it immediately on things from the black market, but by chance I had intel at about 300 going into that mission (playing on normal). Was I just missing the options the rest of the time or is it really the case that this is the only mission you can spend intel on?