But please be aware that publishers often use the xpgt file to specify a large space at the top of the first page of a new chapter, so that the chapter heading appears e.g. a third of the way down the screen. I guess they think it looks more like a pbook that way. In the xpgt you have this:
Code:
<fo:simple-page-master master-name="single_column_head">
<fo:region-before extent="8.3em" />
<fo:region-body margin-bottom="0pt" margin-top="6em" margin-left="0pt" margin-right="0pt" />
</fo:simple-page-master>
The
master-name="single_column_head" is essentially the beginning of a new chapter, and the
<fo:region-before extent="8.3em" /> will in this case put about 8 blanks lines at the top of the screen. In this case we also have margin-top="6em", so that is about 14 blank lines.
If you remove the xpgt, then you will lose this spacing. You may prefer that anyway. You can always put something in the css to compensate, e.g., a suitable margin-top on h1. But that will be more work.
In my opinion, what the publishers should be doing is not using an xpgt file at all, but coding the css appropriately, after all it is perfectly able to cope with this and the xpgt is just redundant fluff, unless you happen to have an epub that relies on it.