Interesting idea, good thinking!
Does it catch junk without bypassing?
Oh, are you not using the weir door?
Pretty important, in that they reduce vortexing, causing air to enter the system.
I'm not seeing the seam you speak of, am I missing it in the photos?
I know our Intex doesn't have a horizontal seam except right at the edge, so high it wouldn't effect knocking out a hole for an agp skimmer.