You are right Birds, not that it would change by that much and I cant seem to foul the plugs no matter how rich I go. From my experience you can run a little leaner due to having more volume of fuel cooling the pistons, my latest tune adds only 18% not 30.
We have been on "winter" blend (e70) since the pumps went in, im not sure they will switch anything till next summer, if at all. There is certainly no power loss having a bit more petrol in the mix, if anything it helps ignite the ethanol quicker improving the burn. Personally I hope they just leave it e70.
OP, what's all the drama about? Man up and get on board, its the only way Caltex will roll out more pumps...