Steps are no different than using Swapactionbar. I can throw all my spells/macros on slot one of every bar in game and tack /swapactionbar on and 1 is suddenly hitting a different macro every time.
As far as the "do not advance for" thing, I'm not particularly for the ISBoxer version of it, but you can still duplicate a version of it using armor slots via the ingame macros or by using nulled castsequences with a reset conditional that you call in another macro further down your sequences such as -
Macro 1
Macro 2 {or 8 or whatever}Code:/castsequence reset=target Corruption, nil
/swapactionbar 1 2
Easy-peesey.Code:/target pet
/targetlasttarget
/cast Shadow Bolt
/swapactionbar 1 2
Having used these setups on solo toons that I didn't want to set up a HKN script for, the only difference is it's way easier and more elegant to do it externally, especially with multiple toons. All things considered, I don't find those actions grey at all since they are functionally identical to actions I can take with the ingame tools.
People get caught up in banwaves and people get it cleared on appeal. Some people also assume that multiboxing is a get out of jail free card for breaking other rules, but they never want to admit that.
You yourself claim that you've been contacted recently by GMs after you've been reported all week, so I'm far more of the mind that a ban wave was in the works and GMs trying to rush through confirming or clearing the who-knows-how-many reported and/or flagged as hacking/botting accounts {which we all know is what multiboxing gets reported as} and slack-assed the check so they could move on to the next ticket.
It's not "people got banned for boxing" it's boxers getting caught up in a banwave. That doesn't instantly equate to us doing anything that is automatically flagged, it could just be manual reports and lazy or uninformed GMs, like it usually is.