1) Fisher is awful.
2) This isn't really some sort of crazy secret, it's just accounting that most people that talk about the cap already realize. An extra year to spread the hit. That's all he's talking about.
His word choice is weird though, this isn't magic and I don't know why he's making it sound like it. Whatever you decide to restructure, you will pay. You don't "save" anything, you simply move it.
Numbers don't magically get deleted off your ledger, but you can rearrange them.
Anytime you're restructuring you're kicking the can, not sure why he said you aren't here. If it allows you more flexibility, great. It all depends on what your goals are and what you want to accomplish.
In general, restructuring your solid players is considered a worthwhile move because the same amount next year, and the year after, are proportionally smaller relative to the cap than they are today. The problem comes when you're irresponsible or major injuries occur. Generally, a restructure here and there are fine and even smart, but you want to hedge some risk by not going crazy with it.
I wouldn't restructure Dez unless I felt completely confident about keeping him, have fielded possible trades for him already, or if there's absolutely another player I'm pursuing hard in FA. If there's any chance of a cut, then no, I'm not keeping him on the books longer than I need.