[adpd]

AFAIK, the single-handed backhander can be hit with more power than the double-hander.

However, the single-hander is tougher to execute when under time-pressure compared to the double-handed backhand (given that you should hit the ball further out in front on the single-handed backhand, and it is possible to have a good contact later for the double-handed backhand). It is also difficult to execute well with higher balls. Given the amount of top-spin that exists in the modern game, this makes the single-hander a tough choice to stick with.

If anybody saw Stan Wawrinka hitting through Federer (my current favourite player, and arguably the GOAT) and Djokovic to claim the French Open this year, you wouldn't say that the single hander is weaker than the double-hander.

And I would suggest that Federer is the last of the great single backhanded tennis players.

* Edited to add a bit of additional info around contact points for the single- and double-handed backhands.