The 'xls' (ms-excel) serializer in cocoon has a built-in limitation that will make it ignore style-regions (and their applied formatting) larger then 2000 cells.
The effect of this is that e.g. dates inside the resulting xsl will show up in their 'general' number-format rather then the appropriate formatting
as soon as the resultset exceeds 2000 rows.
We could prevent this by introducing smaller style-regions through the usage of the intermediate xslt-stylesheet.