Deception is good in poker. Being readable is bad.
The guys with neon signs over their heads blinking away have a tough time getting paid off.
So, I have nothing critical to say about the specific strategic components of deception that have been put forward.
Rather, my concerns are about deployment of this advice, about when it is useful and when it may not be, about whether it should be tempered based on who's sitting around the table with you, and whether following it can actually cost you in the long run.

Mix your game up by mixing your game up.
Make the occasional surprise raise UTG with 7-5 suited.
Reraise in late position with 9-8 every once in a while.
Push a missed flop by firing two barrels to neutralize someone trying the "float play" on you.
This will be sufficient to make your game appear mysterious and you hard to read. Avoid "fancy play syndrome."
Go for "tight-aggressive with a twist".

mac°

Craxer is right for it at the lower limits. It's so easy to just sit down a 10NL table, sit around for an hour waiting for a few big hands and on those big hands get paid enormously. People don't see how you have been playing, plus, at these lower tables there aren't many regular who play for a few hours straight. Most will sit down for 15 minutes and then leave again so normally you haven't played that many hands against them for them to have a good idea of how you play.

When you get higher it's normally better to do what you say muck. 75s is always a pretty nice hand to see a flop with though, you either win big or lose not too much. Higher stakes is all about aggression, the most aggressive player of the table will pretty often win the most money. Just look at durrrr, OMGClayAikon, Ivey and Hansen for a few examples.