Every one likes to claim they are the first.
However New Holland do mower attachments, flail, rotary , & extended reach for their skid steers including the tracked skid steers.
The contractor who maintains the verge & vegitated median strip on the motorway near here has been using one for at least 5 years.
He has a flail on a tracked skid steer because it can do the entire verge , cross creeks, run along extreme slopes and not slip sideways onto the road.
I asked him about the flail attachment & he said he had to go that way for insurance because the rotary would throw too much debris on the road.
And I rather think Ventrac have been doing tracked remote controlled mowers for a while.
SO not exactly a new idea, new application perhaps.
OTOH it would need a really good suspension seat and massive hydros, tracks gobble up the power.