Too tall and too heavy. The most vulnerable part is now the logistics train that must follow it. The tankers can be taken out by RPV’s and by 2015 even insurgents will have RPV’s.
The twin tracks are outdated. You can have 4 half-tracks spaced apart like wheels on a car instead...and then if one tread is blown off the tank still moves on the other 3.
Not so if you lose a tread on a twin tracked tank.