I got a device called a "Kill-aWatt", which anyone can get at Dr Foster & Smith. It measures power consumption over time. Here are the results for my 2 ODNO setups:
This arrangement of two GE electronic ballasts driving two 4-foot 32 Watt T8's draws 140 Watts (1.13A). Each lamp is rated at 2,550 lumens, and light meter measurments show the ouput doubling, so this setup yields 10,200 lumens.
So for 4X ODNO you can't just multiply the 32-Watts times four, at least not for the GE ballasts. If you read GE's own literature, they talk about "Active Current Regulation", which limits the current to the the other three lamps if one of the lamps should fail (remember, this ballast is supposed
to drive four lamps). So when you hook up all four output leads to a single lamp, you are probably causing the electronic ballast to adjust the current downwards, so the circuit consumes less power, yet you still get the doubling of light output that 4X ODNO gives you.
This setup draws 60 Watts (actually, 59). Here we have 4X ODNO driving two 15-Watt lamps in series. When I measured the light output with this setup, I found the gain to more than double, actually 150%. So with four GE "Sunshine" lamps rated at 620 lumens yoiu get 4 x 620 x 150% or 3,720 lumens for your 60 Watts.
This is good news for ODNO users. You are getting far better efficiency than you think. You can't just multiply the Watts by 4 (for 4XODNO), the power consumption is far less than that.