This particular stroke is very difficult to perform, let alone to pronounce. Timing is of the essence and technical ability is there to follow. I found a few video's of two of the top players in current badminton.
Lee Chong Wei
On the 17th of March 2009, Lee Chong Wei and Kenneth Jonassen were playing an exhibition match for the inauguration of a new badminton sports hall in the town of Pécs in Hungary. In the second game Lee Chong Wei (LCW) performs two times the stroke you want to learn:
On the YONEX ALL ENGLAND BADMINTON CHAMPIONSHIPS 8th of March 2014, against Son Wan Ho in the Semi Final:
A training session in preparation of the Yonex All England 2011:
I tried to capture the essentials into the drawing I created:
Like the reversed slice (cross) dropshot, the intention is to make your opponent think, you're hitting a clear or dropshot. With the reserved backhand slice drop shot, your opponent will think you're trying to hit a clear (as Jonassen thought twice). Key is to put in the same amount of energy (racket motion), as to hitting a clear, but at the end perform a reversed slice.