The description of Schubert’s use of alla breve (cut common really rankles with me) is interesting.
Nevertheless, my interest is mensural notation and the ability to use alla breve and common time as forms of imperfect tempi such that I would like to have more than just the option to have alla breve for 4/2. There are times when I would like ‘common time’ for 4/2 in the transcription of Renaissance music. It’s a shame this isn’t a ‘cycled’ choice rather than an on/off switch.