It's hard to see details since the video is kind of blurry, but agree with barrelracer23.
From barrel to barrel, you should be making perfectly straight lines. No arcs. It's science = the fastest path between two points is a straight line.
I would give yourself a little bit MORE room on your pocket, when you come into the barrel turn. It looks like you might be coming in kind of tight, and thus having to leave the barrel wide.
Go back to trotting and slow loping the pattern so that you can practice getting it right.
∞•*˚ Βгįťţαňγ ˚*•∞
It is not enough to know how to ride; one must know how to fall.