I think this is a good change that will make people much more comfortable mapping muzukashiis. I'd like to add another layer to it, though.
Muzukashii break guidelines were handled were a bit fudgey when they first came out, and nobody bothered to "fix" it. What I found interesting is the following:
For kantans, "Main snapping should consist of mostly 2/1, 4/1, or slower rhythms" and "At least 1 rest moment that is 3/1 or longer" is recommended per guidelines.
For futsuus, "Main snapping should consist of mostly 1/1, 2/1 or slower rhythms" and "At least 1 rest moment that is 2/1 or longer" is recommended per guidelines.
For muzus, "Main snapping should consist of mostly 1/2, 1/1 or slower rhythms" and "At least 1 rest moment that is 3/2 or longer" is recommended per guidelines.
For onis, "Main snapping should consist of mostly 1/2 and occasional 1/1 rhythms" and "At least 1 rest moment which is 1/1 or longer" is recommended per guidelines.
Notice how muzukashiis are the only difficult that recommends a rest time that is longer than the longest recommended main snapping (for kantan, 3/1 < 4/1, futsuu, 2/1 = 2/1, and oni, 1/1 = 1/1). I think that this was a small oversight that has never formally been addressed, and this change would be what we needed to address it.
Muzukashii break guidelines were handled were a bit fudgey when they first came out, and nobody bothered to "fix" it. What I found interesting is the following:
For kantans, "Main snapping should consist of mostly 2/1, 4/1, or slower rhythms" and "At least 1 rest moment that is 3/1 or longer" is recommended per guidelines.
For futsuus, "Main snapping should consist of mostly 1/1, 2/1 or slower rhythms" and "At least 1 rest moment that is 2/1 or longer" is recommended per guidelines.
For muzus, "Main snapping should consist of mostly 1/2, 1/1 or slower rhythms" and "At least 1 rest moment that is 3/2 or longer" is recommended per guidelines.
For onis, "Main snapping should consist of mostly 1/2 and occasional 1/1 rhythms" and "At least 1 rest moment which is 1/1 or longer" is recommended per guidelines.
Notice how muzukashiis are the only difficult that recommends a rest time that is longer than the longest recommended main snapping (for kantan, 3/1 < 4/1, futsuu, 2/1 = 2/1, and oni, 1/1 = 1/1). I think that this was a small oversight that has never formally been addressed, and this change would be what we needed to address it.