Hi CipherHost, thanks for you detailled answer! Very much appreciated!
And how cool is it that the amps still communicate over L6 link, even without a POD HD. I really wasn't expecting that. Clearly, adding the POD HD gives a ton of flexibility but for those who just want a basic dual amp setup, it's nice that the L6 link also accommodates that.
Thanks for pointing out the behavior af a standard footswitch in that scenario. Personally I don't see a huge drawback in that. I would probably use the same channel in each amp anyway and use a boost pedal for leads.