Use of 'as per' vs 'per'

Solution 1:

Among meanings for preposition per, wiktionary.org includes

in accordance with [e.g.] I parked my car at the curb per your request

It defines as per as a preposition meaning "Consistent, or in accordance, with."

Taking Wiktionary as a guide, one can use either form with little difference in meaning, but I think some people will object to such use of per and others to such use of as per.

My preference is for per because most uses of as per that I've heard seem pompous and verbose.

Solution 2:

According to Oxford dictionary, per is a preposition and means: for each and by means of. While as per is a phrase, which means in accordance with.

1. Gas is 2 USD per gallon
2. Send it per express

As per example

1. I made it as per your instructions

Solution 3:

The two are demonstrably different and not interchangeable, witness:

• "As per the forecast, it will rain this afternoon." -- This prophecy will be coming true later.
• "Per the forecast, it will rain this afternoon." -- The prophecy has merely been made.

Using "according "+ to replace the permutations of per, "Per", in this case, is "According to ...", whereas "As per" is "In accordance with ...".

A solid case could be made that the first could also be "Per the forecast it will rain this afternoon.", with the difference lying in prosody; I'm inclined to agree--but the second meaning cannot be evinced using "As per...", and trying to do so makes Old Mother Hubbard sadder.

Long made short: "as per" is not long for "per"; it is short for "exactly per".