charging 2 batteries with a single charger

[Jacks9930]

Has anyone used a "Y" charging adaptor to charge two batteries at once.
http://www.greathobbies.com/productinfo/?prod_id=TGHX1006

 

[hamz9561]

It looks like it should work.

 

[trax de max]

On paper it will cut charge time in half, in reality it wont.