Dancing Scrawled Trigger fish

DOES ANY ONE KNOW WHY THIS FISH BEHAVES IN THIS WAY?
Mauritius, Le Morne September 2016. Dive location: "La Gorgonne"
Scrawled Triggerfish dancing for many minutes in front of my camera and video light. I have never seen anything like this and wonder if some one would know why it behaved this way. I would be very please if some one could let me know about this. Thanks Tony.