Sorry for all the posts, but I am an Electra Dyne maniac/nerd and can't help it. :)
And now I"m going to be "that guy" and quote the manual on the single channel thing:
"While the Electra Dyne appears to most as a simple Single Channel amp, the sparse Front Panel layout hides a vault of circuitry that gives you the power and performance of a Three Channel footswitching amplifier. The three Modes found on the Mode Select mini toggle are each completely separate preamps. They share some of the same tube stages but the signal path and circuitry changes radically when you change from mode to mode."
And not sure if you're aware, but the controls are "ganged" and modify a different range for each channel, which helps with the whole shared-control thing:
"The Electra Dyne ushers in a new era of powerful gig-ability combined with interface simplicity by using ganged (stacked element) pots so that one row of controls can adjust more than one circuit. Custom designed tapers on these pots allow a surprising amount of independence between the Modes. Though there will likely be some settings that create compromises on one or more of the sounds for some – with the controls set in their medium ranges - most players discover a high degree of success switching across the Modes in performance situations."