What do you mean, "doesn't have much use"?
KE = 1/2(2/5•M•R2)(v2/r) looks neater than (and is easier to read and understand than) this: KE = 1/2(2/5•M•R^2)(v^2/r)
Maybe he means people don't use them often? I don't want to explain my illogical thinking pattern, but I have yet to see someone use them, except for the occasional
th, nor have I seen a sub before.
also good on me for writing that trainwreck of a sentence