Here is an interesting video on the tefillin debate. It is important because it touches on the halachic process which is an issue that extends far beyond the confines of hilchos tfillin.
I enjoyed listening not because I agreed with everything he said [I didn't] but because the speaker is extremely articulate and I have a weakness for articulate people. English can be a beautiful language if spoken well. And of course the content was filled with valid points to ponder.
One comment: He rhapsodied beautifully about the kedushas hatfillin and explained that because of the fear we have of disgracing the tfillin with impure thoughts or bodily functions [guf naki], we remove them after davening and don't wear them all day [as was the practice in the time of the gemara]. This is why the Rema ruled that women [who are not obligated] should refrain from wearing them for fear of slipping up and transgressing the aforementioned prohibitions. When the Rambam put his tfillin on in the morning he SHOOK out of awe and fear.
He then related that some years back he gave his own tfillin to a non-orthodox girl to wear [in order to insure that she shouldn't make a bracha li-vatala on pasul tfillin] who was going to wear tfillin anyway. Since the girl didn't know the laws of tfillin [she wasn't religious and frankly most religious men don't know hilchos tfillin either], wouldn't it be better if she would have worn pasul tfillin?? It is almost certain that she will not act in conformity with their sanctity so better she not wear. [The bracha li-vatala is less of a problem as I elaborated about here. This article was later published in a kuntres printed in honor of my son Shmuli's Bar Mitzva called Simchas Shmuel which can be found on the Otzar Hachochma].