Problem using unit "mn"

[ChrisSchw]

I am playing a little bit with units and find a inconsistency.

If you are in CAS view and use "USIMPLIFY" or "MKSA" from Units menu (Shift + C) with Time-Unit in "mn" for minutes there, i get an error. I think "USIMPLIFY" expect "min" (like in HOME view), but "min" is reserved in CAS view.
If you use "usimplify" instead of "USIMPLIFY", then it is working.

Example:
USIMPLIFY(5_mn+10_s) --> Error
usimplify(5_mn+10_s) --> 310._s

What is the difference between "USIMPLIFY" and "usimplify"? Same with "MKSA" and "mksa".

Thanks,
Christian