A Chabad rabbi told me that even though I wear a normal belt, I can wear a secondary shabbos belt in the following way. I grab the back 2 tzitzit and bring them around and over the front 2 tzitzit and then use the secondary shabbos belt to hold them in place. I was under the impression the function of the shabbos belt had to perform what would be considered a normal everyday function. I don't normally wear my back tzitzit over my front and thats why I am confused as to why he said it was acceptable. Anyone have an opinion on such a ruling?
See Shulchan Aruch HaRav Orech Chaim 301:42, at the end of the halacha. There, it is explained that one may wear two belts if each one is accomplishing something, and the wearer therefore derives benefit and satisfaction from it.
Without being able to read your rabbi's mind, it appears that he was telling you that if you use the secondary shabbat belt to hold your tzizit in place, than you are using it to accomplish something that your primary belt is not. Therefore, it would be permissible.