On paper, yes, not sure where you want to show that description, if you are hoping to show that description when you open a saved search, then I don't think that would be possible, to be able to show that banner; you will need to be able to deploy a UserEvent script to the saved search record that will read/search your custom record and display the desired banner, however that is not possible, you can't deploy scripts to the saved search record itself.
You may be able to get away by building a Suitelet that would load all your saved searches and description from your custom record, and show them on a table, and then have a clickable link to open the desired saved search, you will be essentially re-creating the list/view of the Saved Searches with your own custom Suitelet.