I listen to all of these people and a lot of them don't know what they 
are talking about.  If you have the energy to do Chansey's double-edge 
and you use it, he has 40 hp left.  Multiple amounts of Pokemon can do 
40 damage and more during their turn.  Has everyone forgotten you 
can't do anything after you attack?  That means you can't heal your 
Pokemon.  And I hear all of this crap about Poke Centers.  Has anyone 
read the card?  ALL energy on ALL of your Pokemon are DISCARDED.  You 
can't sit there with a Chansey out front and build up your benched 
Pokemon and then sit there and Poke Center!  The majority of people 
use double colorless to put on their Chansey's.  An energy removal 
gets rid of one double colorless and a super energy removal gets rid 
of both of them.  Although I agree that Chansey is a good stall 
Pokemon and you can use scoop ups and super potions, the fact is, it 
is hyped up and not as good as you want it to be.

J M