Dividing Anubias nana

My Anubias nana has grown into the wall of my tank and is now squishing up
against it. What's the best way to divide it? I seem to remember someone
(Karen?) saying I need to make the rhizome cut clean and sharp ...

While I'm on the subject, this same A. nana has been growing steadily and
flowering continuously since the beginning of this year, but it is putting
out smaller, paler leaves. It started in my tank as a rather large, deep
green plant with leaves over 2 inches long and two flower spikes. Any
suggestions for nutrients or other care to get bigger, darker green leaves?

Thanks in advance.

Greg. Tong
San Francisco, CA, USA
gtong at sirius_com

"Every infinity is composed of only two halves."