Try tossing them in a micorwave on high for 4 secs. If you have a large amount of them you have nothing to lose from doing it to a 4 polyp frag. I believe the morph is brought on by stress.
Typically they go for about 50/polyp. Never seen them for anything less than 40/polyp. Via club-zoa.com, true PD's have a moderate growth rate.
You can get better deals when you buy them in packs. This guy MarvinsReef has insane palys here... http://www.club-zoa.com/classifieds/showproduct.php?product=87&cat=10
BTW, I saw some photo people posted on RC, I am not sure that photo was taken under actinic only. But the color of the photo was definitely enhanced by bumping up the saturation. The photo was used by a web site that sells this kind of Paly.