I went to school here in the UK, getting good marks in English and I have never heard of the Royal Order of Adjectives. It sounds like some official lackey the Queen might call on when she just can't find the right word.

I remember our English teacher giving us one single lesson on conjugation, and that was only because we were so confused by all the stuff about conjugating verbs in French class. Other than that I cannot remember us going near any kind of formal grammar.

edit - I just thought, it is also not that hard to construct a context in English where 'old little lady' can work.

I looked again at the little lady sitting across from me. At first, from her height, I had assumed her to be young. However now, looking closer, I could see she was a very old little lady indeed.