Let's go mermaids! Let's go mermaid's!

The story:

I first heard the song on a mix CD of party songs a friend had burnt for me.
Later that evening at a party, I vehemently argued for half an hour against the other people there telling me the voices in the song were actually chanting "Let's go Murphys!", and asking me to stop singing the misheard lyrics at the top of my voice. It took an Internet search for the proper lyrics to convince me.
In my defense, at the time I was under the impression that there was an american football team called the "Boston Mermaids".