Originally Posted by chaadster

But of course the tire type does have to do with the conditions of the flat, and it’s simply unlikely that a punctured, or even cut, tubeless tire will rapidly deflate like a punctured tubed tire, or punctured tubular tire, will. It’s precisely the design of a tubeless tire and rim to hold air, unlike a tubed/tubular tire and rim which will not hold air at all if the tube is punctured. Furthermore, without any sealant to slow or stop air loss, tubed/tubular tires will deflate rapidly, with probable catastrophic impacts on handling. Due to the dramatically slower air loss rate of tubeless tires, loss of handling and control takes much longer, giving the rider a significantly bigger window to understand the condition (both feel of softening tire, and often, the telltale hissing of the puncture as sealant goes to work) and avoid dangerous situations.

Unlike relying on a flat tire to keep a rider from sliding out on an extremely slippery rim-to-road interface, a tubeless tire will go soft but still afford pneumatic grip long before it loses all air pressure (in most cases) and is far safer for that fact.