When executing fontbakery check-universal on a VF generated with the “Disable Masters” CP, I get fails for some checks :
com.google.fonts/check/varfont/regular_wght_coord
com.google.fonts/check/varfont/regular_wdth_coord
com.google.fonts/check/varfont/regular_slnt_coord
com.google.fonts/check/varfont/bold_wght_coord
com.adobe.fonts/check/varfont/valid_default_instance_nameids
I believe the issue might be that the axes which were removed (due to the use of “Disable Master”) are still present in the Axis Location sets.