Help understanding CV in Mach

I have fought intermittent jerkiness issues with my machine running certain files. This issue pops up when I import a file that was created not using true arcs but rather line segments. Today I turned off all the check boxes for Mach CV and turned up my look-ahead to 200 lines. The machine ran a the job smoothly.........what detrimental effect (if any) will turning off the CV have on my cuts?

Thanks,
Scott