If you watch the "blue scenes" very closely, 
you'll see the OP cels aren't reused. This *IS* 
definitely a copy of the OP cel - line for line 
(see my screen capture) - but is obvioulsy not 
used in the OP and that frame is used nowhere in 
the anime BUT the OP. (I went through the "blue 
scene" on frame advance to be sure.)

Maybe the studio intended to re-use the douga 
from the OP for the ending fight then junked the 
idea? That I don't know, but here's a bit of food 
for thought: I have almost 100 Psychic Force OVA 
cels, and every one except for *two* came with 
matching sketches. . . The two that are missing 
sketches are my only two OP cels of Keith from 
that same sequence. I once saw a third cel from 
that sequence for sale - it was also missing it's 
sketch. Coincidence? Most likely not!

Hey, I think you might have just answered one of 
*MY* Psychic Force questions!!! ^_^;;

Many Sharp Smiles,
--Drac (wishing she had one of those sketches!!)