That's what I did and I found that it was actually enough for a 10% hit in EU output. That's pretty significant.
What I noticed, is that, the tank with the regulator is updated more frequently than the tank with the pipes.
I had the impression that Greg pipes output about 2 times per second, while the regulated tank keep the marker running.
An easy (maybe) way to fix it (I think), and make regulators less relevant, would be to make the turbines check and consume fuel each second, instead each tick.
So, a tungstensteel turbine will check the hatches each second for 20000L of steam and consume it, instead 1000L each tick.
That would make it way more intuitive.