Thanks for the reply, Curunir.
I just tested the reactor itself, and tuned it so that it burns just hot enough to produce around 16.5 B/t, which also balanced my water/steam within the reactor, as you mentioned.
According the the TE3 wiki, tesseracts no longer suffer the loss to transfer, so I'm assuming the transfer rates are complete.
I have already tested the setup by deactivating all of the reactors, waiting til they spin down fully, then spun them up/spun them down individually to see if anything changed. Sad to say that it did not. Even with the steam reactor fully powered, the four bottom turbines still only spun up to the afore-mentioned speed.