I think poster dontwastetime wastes lots of time on speculation when a simple search on google would show how much time he is wasting on this, geech.
Doesnt matter that you think the church wouldnt allow this, it is clearly explained in many articles.
It's there, go visit Salamanca and see for yourself. It's a tradition to add contemporary stuff anytime there is a restoration. Go read an
architecture blog
Monks of the day used to wear a cowl which covered the head and shoulders. So maybe when the original was repaired, some soled shoes added. Going by
other posts, the artisan had a sence of humour. TC.