Adhesive softening & replacement for Front Glass/Digitizer Replacement

In replacing the Front Glass/Digitizer at several points adhesive is softened prior to disassembly. Particularly step 5, 9, 11, & 18.

Is the iOpener to be used prior to each of these steps to soften the appropriate adhesive?

When replacing the glass (and digitizer if I break it) do I need to reapply adhesive? How about the other adhered parts?