The automatic turbomode will always be activated, when no gaps are in the files to be renamed. Then, every file will not be renamed twice (to tmp. and then to it's real new name), but only once (immediately to it's real name). In this case ProRen will only take half the time to rename files.

If there are Gaps between the files to be renamed, the files are renamed twice, because it's not to 100% decideable, if there will be a collision or not. It's even harder to decide, if the user shall be asked for each gap.