I have long argued that certain Ringen techniques require you to grip your opponent's clothing.
Roger Norling of Gothenburg Historical Fencing School agrees, and has compiled a series of images from the Ringen chapter of Mair's Vienna manuscript that clearly show belt, sleeve and crotch(!) grabs.
Check it out here
This is proof-positive that the Ringen community should be training in a BJJ gi or similarly simple, durable, function-over-form grappling jacket, regardless of whether it looks "too Asian."
[Edit: To clarify, we should be training in gi/kurtka unless and until
a ringen jacket appears on the market that is equally durable, comparably priced (under US$100), easily adjusted to fit different body types, and appropriate for competition in events that have an open "gi" category. I have yet to see a product that meets those specifications].