The tentacles just don't look right in their orientation. The corals in that article have tentacles oriented in a ring around the mouth. And there is a distinguishing circle just beyond the mouth area that marks the tentacle ring.
This picture shows the ring just beyond the mouth (but with tentacles hidden) pretty well:
http://www.advancedaquarist.com/issu...3/invert11.htm
This picture shows the tentacles in the ring shape:
http://www.advancedaquarist.com/issu...3/invert10.htm
Both pictures are of the indo type
Notice in both there are no randomly placed tentacles. In the picture we have to try and ID here, the tentacles are kind of random and are placed all over the coral. There isn't any ring of tentacles, just a mouth. More like a fungia