VR, V/R, R/, R, and Vr, ???

I understand the intent of these closings, but am not sure why the / is ever used, as you would never close an email with

Very/Respectful, Respectful/, or Very/respectful. Instead, it would be appropriate to close with-

Very respectful,

Respectul,

or even-

Very Respectful,

So, my question is why is the / used at all?

Lastly, and this is just my two cents, but I would strongly encourage every retired, or even current, member of the military to always use VR, Vr, V/R, or whatever variation you use, when closing an email to any civilian, as it's always good practice to humble yourself and show the same respect to the janitor as you do the CEO. Having spent 7 yesrs in the Army, I certainly understand the necessity of respecting rank, and never accepting a lack of adherence to the structure, but I feel it's equally important as a civilian, or a human being in general to show everyone the same degree of courtesy and respect. Therefore, I'd never use R/ or R.

I digress... Please explain why the / is ever used in closings.

Thanks, in advance??