Complex sentence: "Cut sketches" are those sketches that were either filmed but ended up on the cutting room floor for reasons that include time constraints, or those sketches that were ditched at the early scripting stages and were never shot.
Split into simpler sentences: Cut sketches are those sketches that were filmed but ended up on the cutting room floor for reasons that include time constraints. Others may have been ditched at the early scripting stages and were never shot.