In this case the extra hash marks are around the trim function: #trim(form.fieldName)#
In dreamweaver MX / MX 2004 you can highlight these # signs.
click Edit > Preferences > select Code Coloring > select Coldfusion > click Edit Coloring Scheme > select ColdFusion Script Bracket > click the "B" button to make the selected text bold* > click OK > click ok again on the preferences box.
*You can also change the color if you like, however it also changes ( and ) and [ and ] inside the coldfusion tags. In my opinion I thought it was more of a change to what I'm used to just to highlight a pound sign.
Your code will now be colored like this making it easy to identify extra unneeded hash marks. The bold pound signs below can/should be removed for best practice.