Chahouas will only regrow a pointed stump (sorry, taking this right out of the Rhacodactylus book) if it drops from the base. If the tails breaks further from the base, it'll grow partially back.
They are also the most reluctant to drop their tails out of all the rhacs.
It's a GREAT book, but just a warning, it has the most information about Crested Geckos and Leachies.
And not as much about Chahouas, but that's because they don't differ too much (as far as care goes) from cresties.
I have read in the same book that Chahoua's have stronger tails than other Rhac's and that they lose their tails less frequently. I haven't worked with them (so sad ) so I just took that out of the book...