The same thing that'll happen if you field an IS-2 against two Panthers.
If your opponent's gone all in on tank destroyers why are you calling in a Tiger?!
A double Jackson build has thrown ~40% of its popcap into vehicular anti-tank. You beat it by exploiting its relative anti-infantry weakness, not by building the things its good against.
That's the Elefant.
Nice theory but it completely wrong.
M36 can be disembarked in which case the total pop is 8.
(even when crewed M36 has a pop 16 so the total is 32% not 40%)