Are Heavy Tanks SLOW?

[CSSS]

I know in real life Tanks were transported near to the front as possible via train or motorized carrier. I have played as Axis for a few goes now and
the allies usually overwhelm me sometime in 1943 if I give them any advantage exp or bonus, which in itself is awesome. However when I did buy and receive my heavy tanks they moved slower than
a dual amputee infantry unit, and their effect at the front was extremely small. I have played all SC from 1 up the development of this version is excellent, yet I must be missing something as to play style.
In SC 2 I could set the computer at +100% and +2 and stil slaughter it. Now I am about to play my first equal game no bonus to the AI at all. Still I feel I am doing something wrong? Is it me or has the A.I so improved as to being tough?

[n0kn0k]

Next release they should have one more AP as Bill said in another topic. They can't keep up with infantry atm.