I'll have to see how far the hinge needs to go up to be able to comfortably remove and insert a piece of film.

For a changing tent the tape might work better. The film lifts off pretty easily and the tape remains tacky enough to use a couple more times. I Run the tape right along the long sides of the holder in 4 inch pieces and one piece at the top and bottom. Apply pressure gently with a cotton glove being carful to touch only the 1/4-3/8ths of an inch contacting the tape. (the same area that would normally be under the rails in an old style holder).
As long as you stay on this width with your pressure you will have no marks on the image area of the film. (although gentle pressure with the cotton glove should leave no marks.) This is how I have been working with the holders.

The nice thing about using the tape is that it allows the use of inserts in a holder so multiple formats can be used without the need to carry additional camera backs. For example, if one had a 12x20 camera, a set of inserts could be used to center 7x17 or 8x20 or 11x14 film in a 12x20 holder. With one camera, one back and 4 holders you could go into the filed and shoot 4 different formats.