Naysayers, already! Can’t be done! Bah, I say. BAH! 
In the science of Workflow Analysis there is the concept of “state” and “transitions” (“finite state machines” if you know the jargon). Let’s say you are at a classic “2 decks & a mixer” workstation and have two tracks running in sync. At any moment in time there are a finite set of operations you can do next: from where you are you can crossfade, tweak FX controls, stop a track, pitch up or down, etc. Many of those operations are short events that leave you pretty much where you started ready to do another tweak - as soon as you change a filter value, you are free to change it again. A few of those operations are more involved, like stopping a deck and taking the record off. Once you’ve committed to that operation your workflow is pretty linear - you’ve got a certain amount of time to put away the old record, find a new one and get it cued up. During that operation there is a slight chance you may want to tweak a filter on the running track, but you will definitely never going to be altering the pitch control on the silent deck while you’re diving into your record bag. Why would you bother? This is the concept of the “Two Hands” rule - you are never going to be using all of the knobs at the same time, there is a physically limited number of events that you can be operating simultaneously. (Computer help you add more events to that list by looking after things for you, like running Deck C, and this is the beauty of machines.)
The sounds coming out of your setup are called the “states” and the operations you have to go through to get to the next state are called the “transitions”. A good controllers job (and the software too) is to make these transitions as painless as possible so you can get down to the job of making and shaping sounds. These kinds of things are often diagrammed as dots connected by directed arrows, the dots are states, the arrows are transitions. RULES OF PLAY: Once you take a transition you can’t go back unless there’s a different arrow going in that direction (a “directed graph”).
Looking at the problem from that point of view, having a TriggerFinger set up beside your decks is great for the short, open ended events - you have many more of them at any moment! These are short events are diagrammed as little circles that that loop back to the current state. The TriggerFinger does nothing to help you do the more involved linear operations, which is also the place where the software often forces you to reach for your mouse and go interact with your DJ software - get mouse, move to the finder, select a song, right-click, select “load on Deck B”, wait, done. (Ableton Live helps by allowing you to preprocess some of this stuff into sample groups that you can preload into the grid, but these advantages are offset by it’s painful file finder, so it ends up about equal IMO).
I am betting that if you did the analysis with a good number of DJs, once they’re into their flow I would expect to see similar work patterns for their major tasks: lots of short transitions, a few set piece bits they’ve rehearsed and a lot of basic shuffling through the linear tasks. Yes, each one will have their own flavor of embellishment (Moldova’s sample & reorder controls for instance), but my thinking is that the extra controls on your controller above and beyond the basics is where you map these personalized embellishments. In my view it’s essential that controllers have more buttons, sliders and wibbly gee-gaws than strictly necessary, otherwise you will have nowhere to stamp your style on a set (which is what leads people to add TriggerFingers and knob boxes to their setups!) The Otus guy understood that in the video.
So, a bit handwavy for a grand unified theory of Controllerism, but I don’t subscribe to the “You can’t please everyone” camp. Maybe not immediately, but I think we can do a lot better than we are right now by thoughtfully applying Workflow Analysis.
Wow, that was long. I’ll shut up now.