separator row or multiple lines

I have read the archived solution of this problem to include rows in the source data with blanks cells except for the subtotal labels and amounts.

I need someting though that will allow multiple breaks in the grid data where information headers appear that would need to span a couple of columns. I could put multiple grids on the page and make my descriptive headers in html but this is not the prefered solution in my specification.

Ideally I want to insert a row at row number x. this inserted row would have one column filled with html label elements and it's height tall enough to accomodate the descriptions.

Can anyone help? thanks