We need to stop treating all 1hbhs as the same thing.
I think tennis elbow is much more likely to happen when players use the Continental and Eastern grips.
Furthermore, many recreational players who taught themselves the 1hbh use grips that are in the continental range (in fact, I've seen many players just use an Eastern forehand grip on their 1hbh!).
Thus, I think it's likely that many of the cases to TE we might see are due simply to an excessively weak grip, even if it is Eastern.
Players that use an Extreme Eastern (8/1) make contact much further out in front, which creates a stronger arm structure at contact and also reduces the tendency to muscle or wrist the ball.
In short, I think it is a mistake to treat all 1hbhs the same. The liabilities of the 1hbh are much mitigated, or possibly eliminated, by using an Extreme Eastern backhand grip.
Thus, compared with the other 1hbh grips, using the extreme grip:
1- Reduces susceptibility to tennis elbow
2- Generates more topspin and thus more consistency, and often more power
3- Increases the strike zone, particularly for high balls
4- Reduces the forward-back footwork requirements (because of point 3)
5- Is easier to learn because of 2,3,4; and because opening the body is more natural both for the grip and for the player; and because acquiring a good slice backhand is not as essential (because of 3 and 4)
and as a bonus,
6- Allows most small players to generate more consistent power than they would with a 2hbh.
Let me end with an analogy -- Imagine there were only two types of forehands under consideration: A continental-grip forehand (like McEnroe, Edberg), and a 2-handed forehand (SW bottom grip, like Seles). Which stroke would be the preferred modern forehnad among players and coaches?
I'm guessing that the 2hFh would, and people would be talking about how the 1hFh is obsolete.
Of course, the 1-handed Forehand is not obsolete when we take into account the SW grip.
Same idea with the 1hbh.