There has been controversy over questions regarding the Carmelite Scapular - and it is to be noted that this document that is often suggested in the forums- The Catechesis from North American Prov. (I myself have suggested it in the past) is from 2000 from the Provincials of one area of the World. It contains an interesting discussion and details but it is what it is - not something more than it is.
Since then this came out from Pope St. John Paul II:
w2.vatican.va/content/john-paul-ii/en/speeches/2001/march/documents/hf_jp-ii_spe_20010326_ordine-carmelo.html
Where he interestingly celebrates the 750 annv. of the “bestowal” of the Scapular.
A more recent letter (2015) from the Prior General of one of the Orders (O.Carm).
carmeliteinstitute.net/solemnity-of-our-lady-of-mount-carmel-2015/
“A third point is that this year we celebrate the 750th anniversary of the death of St. Simon Stock. Of course it is true that the figure of Simon Stock is enveloped in the shadows of the Middle Ages, and historians have found plenty of material to study and debate. However, according to the tradition, and without getting into any controversy, Simon died in Bordeaux on the 16th of May, 1265. That is why this year we record the 750th anniversary of his death. Simon Stock is tied to the tradition and piety of the Carmelite scapular, and for that reason, it is not out of place to be reminded of this central element of our charism that unites us to Mary, Mother and Sister of all Carmelites. Please God, we, like Simon Stock, may turn to Mary, in our moments of sadness and discouragement, in our trials and disappointments, so that she, first teacher and first disciple of our Lord, may help us to journey as disciples and witnesses of the Good News of the Gospel, especially in our proximity to the poor and needy. The Carmelite scapular, in all its lowliness and simplicity (and perhaps, precisely for that reason) continues to be a reminder of our commitment to the values of the Gospel and is a seed of hope.”