I nuked my account back in December and started over. Last summer I had studied the first part of the New Practical Chinese Reader so I recently decided to go back through that list. I was shocked and amazed at the things I remembered, even though I hadn't reviewed them in four months or more. Some of the stuff I remembered was completely random, like people's names. Even the stuff I forgot was not too far from recall, I just had to refresh my memory a little bit. Amazing...
The nuke was the best thing I ever did, by the way. It let me start over with a much clearer focus on high-frequency and/or useful characters and words.
There was a feature request a while back to allow us to see the frequency of characters and words. Is that something that could easily be displayed in the right-hand pane? It would be nice to know when you can safely delete something because it's highly unlikely to come up.
James