I coded it this way only to see if it was possible to use pointers as such in Arduino. 
as for returning the calculation right away, not the variable that holds it, in my opinion, returning the variable that holds the calculations can be easier to the reader's eye. Surely some of us understand it, but the majority may not get it at first glance. Especially if this library is going to be distributed publicly. I have no problem applying both suggestions. I will apply it to the new library which was illustrated in the documentation Mohamed sent and I will submit it here for your approval.