I guess I never thought of it that way. Definetely the reading people goes out the door with online. I don't agree so much with the Mathematics part since I have a computer science degree but I guess since you are playing a lot more hands online then you would at a live game that would probably leave you more supceptable to bad beats or looser players.
By a mathmatical game, I mean most online players of any worth have are using a HUD.
They have stats on the way an opponent plays that are more accurate than could be obtained by simply watching the play. Thus equity can be more acurately calculated against an opponents range using something like pokerstove.
I also have alot more success at Live tables even though I have played online for a long time. I am great at reading people live but have a tough time online because of the vast variety of opponents and styles and unavailability of a true "read".