Whitespace rules

Consider the following query
<a>{<b> </b>}</a>

And boundary-space policy is strip
I can't understand either the whitespace inside <b> constructor should be
discarded  or not.

>From the first point of view it is said:
"Boundary whitespace is a sequence of consecutive whitespace characters
within the content of a direct element constructor, that is delimited at
each end either by the start or end of the content,..."

But after the last example of chapter 3.7.1.4  It is noted that "whitespace
inside an enclosed expression is never considered to be boundary whitespace"

Regards, Leonid Novak modis.ispras.ru