… and here’s the steak knives …
GCodeClean skips a step (or two) v1.0.5 
Sometimes bad CAM will encode cutting paths (G1) that’s actually above the surface of the work (i.e. they should be G0), maybe abuse of cutter compensation etc., but generally 'just bad programming’™️
Running the zClamp pass over the GCode will convert all such bad cutting paths to G0. Then this functionality can do its work to eliminate all of the intermediary G0 movements that do nothing but waste time.
There’s a new command line option --eliminateNeedlessTravelling with a default of true, including this option and setting it to false will let you keep these lines if there’s some perverse reason (like bad CAM) that means you need to keep them.
Release v1.0.5 - Eliminate Needless Travelling · md8n/GCodeClean (github.com)