In proposing novel measurements, which have no prior basis in the Buddhist textual tradition that I could identify, what the Vinayamukha is doing is critiquing a misreading or strawman of the Samantapasadika commentary on the kutikara rule which would place the sugatavidatthi at about 60cm. Or at least, this is what I understand of the Vinayamukha approach.
The cmy itself only states that the carpenter’s hattha, which is 1.5 ordinary hattha at about 60cm, should be used for the sugatavidatthi in respect of huts. This is FAIRLY NORMAL for old-school Indian and Sri Lankan building measurements, although it’s also possible that the ordinary hattha was meant. The cmy is silent on robe measurements. although a broad reading of Indian sources as a whole might suggest that the hattha, at about 40cm, should be used for these.
I feel really bad that the commentary has been treated this way, it’s just a misreading on the part of the Vinayamukha, no sane person would ever use the carpenter’s hattha to measure cloth or as a robe measurement. That’s not what the cmy is trying to say.
May I refer everyone to this thread?