DOCBOOK: DocBook: whitespace question.

I have a question about whitespaces in SGML/XML documents.
I notice that most documents do not have whitespaces just after a tag is
opened and just before a tag is closed.
<para>This is a sentenece.</para>

I prefer whitespaces to clearly seperate the tags from the text.
<para> This is a sentence. </para>

Infact I usually put tags on seperate lines and indent the text for
extra readability.
<para>
    This is a single sentence but there could be many more in this
paragraph.
</para>

I don't have any rendering problems with these so I assume it is OK.  I
do notice that when I use customized entities or other tags, that I can
run into problems, especially when special characters are involved (eg.
punctuation).
<para> I will emphasise the word <emphasis> sentence </emphasis> .
</para>
There is a space before the period which is not correct.
I have to write
<para>I will emphasise the word <emphasis> sentence</emphasis>. </para>
or
<para> I will emphasise the word <emphasis> sentence. </emphasis> .
</para>

Should DocBook recognise that a period comes directly after a word and
remove the space ?

Thanks,
Brendan Simon.