Just checking to make sure you *REALLY* want to do that:

Opening a new <ul> as a replacement for the comment+</li> will result in a nested list... which will be doubly indented and which will require an additional </ul> at some point.

If you're dealing with that, separately, then you'll be fine, but if not, your results may not be what you expect, and your html will surely be ill-formed/non-compliant.