I know this is a strange question, but do UDFs have the ability to
change the spreadsheet's properties? For example, I have a function
which computes a value, but I needed it to merge the cell with the one
below if that value met certain conditions. It doesn't seem to want to
do the merge, but it seems to me that VBA instructions in the UDF are
just that; instructions. It shouldn't matter whether they affect cell
properties or not.

Am I correct, or have the programmers of Excel given it enough
sophistication to know that a UDF is purely for producing a value?

Thanks for any input...