I wired my 770 in the following manner well before the Outlaw’s more recent amps began using a similar scheme:

Main, Surround, Rear, Center, Rear, Surround, Main.

The logic had nothing to do with which transformer taps were being used. After all, the two transformers can operate all seven channels at full power simultaneously all day.

The more important issue in my thinking was heat, and the way to keep things as cool as possible without fans.

If wired as above, hard-driving stereo use will result in heat generated at the two ends of the row – the easiest places to remain as cool as possible with passive air flow.

In 7.1 surround, the channel doing the most work over time is the center. It is bracketed by the two channels doing, on average, the least work. The progression of increasing work/heat continues outward from middle.

If someone were to wire the amplifier in the order Center, Main, Main, etc., they would be grouping the channels with the greater average heat generation together at one end.