[adarmaSen]

Strictly speaking that would be a question to pose in the Mahayana forum but as it hardly merits a thread there, I'll reply here.
The term is used legitimately by those studying the tenets to designate the long defunct Vaibhashika and Sautrantika schools.

I'll re-phrase.

How much do we see this notion used in its "legitimate" context, vs. it being abused and used to slander the Theravada sects and/or the liberative teachings of the Buddha?

...a "ball-park" guesstimate of percentage would do...