questions re WD-xml-infoset-20001220

greetings.

Upon reading the 20.12.2000 draft infoset specification two questions
occurred to me. i would be grateful for a pointer to threads in the
archives which might give me some background to help me to understand
what the infoset intends. i've tried to search on the obvious keys, but
found tangential discussions only.

1. why don't attributes have a parent?

2. why are expanded entity references replaced by their string
equivalent and then marked with start and end markers?

thanks.