Besides the work on the boat, Deb did some homework getting the windows ready to reinstall.
Taping is usually a very important part of any job involving adhesive 'goop' (caulk). If not done properly, cleanup can be the most tedious and time consuming part of a project.
Masking tape is applied anywhere you don't want goop, even the entire glass pane. Taping is just one part of goop-ology.