Altar Server Vesting?

[Yes]

Where is the documentation that states that altar BOYS should wear a nun’s habit when they serve?

Who is suggesting that such documentation exists? Certainly not me. Are you trying to make a point?

 

[Yes]

Not every element exists in the GIRM, which itself never needed to exist before the New Mass.
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It [cassock/surplice] is loaned to Altar boys as a clerical garment. It is thus a male garment. **

lets not get into semantics about this. Altar boys fill in the role of an Instituted/ordained acolyte, which are the only ones who have a RIGHT to serve on the Altar. Altar boys do therefore imitate/fill in for this office because of the lack of Instituted/ordained acolytes - therefore the wearing of the cassock and surplice (and in some places the roman collar also) can be said to be by Indult.

Its common sense women should not wear Cassocks - they can never attain the office of acolyte or become clerics.

Your logic is flawed, and has nothing to do with semantics. One could just as easily say the cassock/surplice has traditionally been on loan to acolytes/altar boys and anyone fulfilling that function (as allowed by the Church) should be allowed to wear them.

Both female and male altar servers “fill in the role of an instituted acolyte.” It would be nice if the Church restricted the wearing of the cassock/alb to males in the Latin Rite, but I don’t see that happening anytime soon.

 

[Yes]

After reading and re-reading your post, it still appears that you are defending the practice of female altar servers using cassocks and surplices and that you were using the use of said garments by Protestants as some sort of justification for the practice… If I misread I apologize.

I’m sorry too – it could have been clearer. The simple fact that MANY lay Protestant ministers (including many time their celebrants) wear the cassock/alb is yet another reason to view their use by some lay members as problematic.