Although, really a song is only new the first one to three times it is sung… after all, the words are hardly new even if there might be repetitions in a chorus-like form - and so there’s really only the rhythm and music to catch onto -
which means that after even only a handful of weeks, almost everyone should have caught on.
I also find that an occasional change - such as the choir singing something previously spoken, or a different style of a regular song - can make sure that everyone is awake at MASS and paying attention…
it’s hard to unthinkingly “rattle off” an Our Father if the way it is said or sung is changed just enough (keeping the same words, mind) to jarr people out of auto-pilot and onto new old ground.
I am sure your choir director had some of her own, likely valid and possibly excellent, reasons to change things up a little and try out something new with your particular parish.
It seems to me unlikely (though I could be wrong) that a person who would do something on just a childish whim would last very long as, if they ever managed to become, a choir director.
If the Our Father is sung like that somewhat frequently from now on in your parish (lucky you!), I suggest that you give it a few weeks and do your best to participate in and learn the new song.
If you feel it would be helpful, you might even approach your choir director, or a member of your choir, and ask for a copy so you can see the notes (even if you can’t read them exactly for singing purposes, you can at least follow them higher and lower once you catch the initial sound) and the order of the words if there’s anything like a chorus and any rearrangement to consider.
I am sure that your choir would be delighted to help you fully participate in the singing of that particular prayer (be warned: you might be asked to joined the choir, or even pressured to do so! it is only because they love singing, and they like/love you and would like to share their joy with you!) - so remember, ask and you shall recieve!
disclaimer: when asking, beware that what you recieve may not be what you meant to ask for!!! example: a child in her anger asked God to ‘go away’, and He in His wisdom came even closer to her heart… thank God!
love,
Saoirse