Haven’t heard any demos yet that were obviously using the filter / LFOs / envelopes – sounds more like manual control of the distortion. Will keep looking.
As far as analog distortion in a recording environment, I recently picked up a Radial EXTC “effects reamper” (no, autocorrect, it’s not an ‘effects reaper’).
This is a nifty box that takes a balanced line-level signal from your DAW/interface, converts it to a Hi-Z guitar impedance, sends it to any guitar pedal(s) that you choose, then takes the output from the guitar pedals and sends them back to the computer at line level again. Or, in plain English, it allows you to use any guitar pedals you have as insert effects on recorded audio.
Besides opening up a world of sonic possibilities, it has greatly relieved my vague sense of guilt at owning all the guitar pedals that I don’t use anymore, as I can now tell myself – hey, maybe it’ll make a great effect on a vocal track someday…