The test proved to be pointless for three reasons:
1) When I tried to fill the internal buffer, a 10000EU starter supply was too big for the internal buffer. When I said that thing was tiny I wasn't kidding.
2) Adding an choke tube and efficiency tube brought the effective power ratio right back to 3:1 instead of 6:2. All I did was halve the speed it outputs power at.
3) It seems Power Crystals added safeguards against power loops as when I tried to loop the power it simply burned through the internal buffer.
So there you go, even before you factor cable loss into it the Electrical Engine will at best match the 5:2 power ratio and power looping is not realistically possible.
I'm not sure why you'd call it "pointless." Data is data.
But you can't use 2 iron (efficiency) tubes? I thought I did exactly this on my DW20 server. The forestry documentation suggests that if you do the ratio would be 3:2. Or so Forestry's wiki implies. The choke is just supposed to be there to address the small power buffer; it doesn't affect the actual efficiency in any way.