Comments on XPointer CR2 section 4

It's my belief that the quoting/escaping rules are too difficult for
most people to get right easily. Indeed, they may be too complex for
implementers to get right interoperably, but that remains to be seen.

I know that the rules were difficult for me to explain in a book on XML,
and I have heard two other authors say the same.

Why can't xpointer use URI escaping with % signs at all levels and give
a list of characters to escape?

Liam