Greetings.
The two cent answer to your million dollar question is, "it depends."
If the attacker, and/or their script uses the administrative shares, and they are not there, then you will most likely be successful for foiling that specific attack. However, if the attacker uses pretty much any other method of attack, which does not rely on the administrative shares, then it was a good idea, but just not effective against this attack.
I think you already knew the answer to this question.
So, may i please have my change from the million, less two cents?