At least it can't totally fail, it IS valve.
Yeah, they were successful in splintering the entire CS fan base. I don't know the exact percentages... but there are 1.6 fans and there are Source fans... If they made the game exactly like 1.6 and just upped the graphics, THEN maybe people from 1.6 might accept Source.
Although, they say CS:GO will unite the two together... (doubt it)