Roger Letwolf, however, they didn't brake off all that soon, but you may very well be right. There were some TA152's that were very at the deck though (Ta152H's NOT one of those).
Sundog, the Ta152H-0 didn't use any MW 50 or GM1 boost at all thus the speed down low of a TA152H-1 will be higher since the H1 used both MW50 and GM1.
The TA152H-0 used a Jumo 213E engine which wasn't ready for these kind of boost systems, The TA152H-1 used a Jumo 213E-1 which was fully ready for these boost systems.
Also, max speed in level flight doesn't quite change with weight, can test it with different fuel loadout, acceleration however in level flight is changed, the heavier it is the more power is needed to pull it. The H1 was quite much heavier but most of the new weight was the fuel.