To me, “Live mastering” sounds like cooking a meal of fresh ingredients, then adding preservative agents for flavor. Or riding a bike while pumping up the tire.
Maybe I’m just an old fart, but I wouldn’t have thought about using these words in context.
It’s probably for lack of a better descriptive, i know.
great advice from the master ! 
regarding plocking/lfo as “fake”
sidechain: i always tthink that it’s not precise like a real compressor in terms of attack and release and my ears tend do suggest that it’s complete off - even if in reality probably it’s not
Plocking is definitely not the same but it does create room and a similar effect.
LFO to amp volume can definitely sound very much like a real side chain compressor. Work with the limitations you have and you’ll be surprised 
Do you use the inverted exponential wave?
Actually on a big sound some of that polish can be completely impossible to hear or worse, can have a negative impact on the clarity of the sound. In a big room with loud PA, some sounds are masked by others (including sounds that are extraneous to your music), and suddenly the complexity of your sound layering falls apart. Another example: these veeeeeeery long reverbs are great and impressive in the studio but they get muddy real quick on stage.
Some effects are also completely useless. Example: In the studio you will try to recreate the high impact of a big sound system, butchering your sound with compressors… while actually this impact is primarily created by the limits of your own ear when the level goes beyond 90dB.
That was exactly the case when my friend and I played the first time in front of people . The reaction was like . „Wow that drums and basses hit hard“. But the PA must be able to handle that dynamics. When there is not enough headroom you can run into the limiter ( that was the second time we play ) and get nasty digital clipping
Re: Ducking with lfos on the Octatrack - I found that I prefer using an inverted exp lfo in one shot mode on filter width (set to 12 db) rather than amp volume to duck basslines. I fine tune it by pulling the lfo speed way down and then slowely increase it. When the ducking effect becomes so fast, that it’s no longer audible, I turn the speed back a nudge.
When tuned right it sounds like a nice exponential envelope attack stage, nicely ducking the bass out of the way. Mute the kick to hear it in isolation.
I usually don’t like using an inverted square lfo on amp volume in sync trig mode, the volume change doesn’t sound nice most of the time. It seems to work for higher freq content, lead sounds etc. especially when they go into a reverb, but most of the time an one shot lfo with inv exp wave work really well, especially on filter width.
This was one of the things I had to experiment with regarding my post about the DN/OT LFOs. I did find that sidechaining with the filter instead of volume sounds better most of the time.
Yeah that works really well. I do this with the DN/DT base/width filter a lot.
AMP vol modulation with LFO I use mostly on things like pads.
I have this one. Works like a charm. Made by Cheesy intruments. All analog 
cool!