Well, upon further examination I realize that the reason you cannot open the angle well is because you never close it.

Look at this position. The disc is like 15" from your chest when, in the Beato picture, Beato is nearly touching his pecs with the disc.
Then here (one frame later):

I will correct myself somewhat. You DO actually achieve the proper opening position (arm to body angles similar to Beato), but since you never closed the angle of the lower arm, you do not achieve the "two feet in one frame" lower arm acceleration that Beato does.
You are literally slingling your slightly bent arm around with your shoulder. It is no wonder you do not "believe" in lower arm acceleration, you appear to throw with almost no hinging in the elbow at all. You kind of crook your arm and just whip it around with your shoulder in a wide arc. I think we have discussed this before... and I said the same thing then too.
Also, note that all the really good acceleration in your throw was *BEFORE AND AFTER THE HIT* not *AT THE HIT*. You can tell this by looking at the frame by frame distance of movement. At the hit you arm barely moves, the frame and after the hit accelerate tremendously, only to see the hand *SLOW DOWN* at the hit.
These are all things you can plainly see for yourself...
Hey, if it works, use it... but there is nothing to be gained by looking for a "magic bullet" of convention, when you really are not conventional. I can show hundreds of "into the hit" positions of top pros and they look nothing like you... You are out of position for a conventional top player, it is just simple. You can argue semantics all you want.
"The reasonable man adapts himself to his environment. The unreasonable man adapts his environment to himself, therefore all progress is made by unreasonable men."
-George Bernard Shaw