I'd buy this book in a heartbeat, if he wrote it.
Anyway, some good advice. RTWT.
I think I've mellowed over the past 3 years or so. The heresy detector is still on, but it comes with analytical settings such as "is the issue really more de gustibus?"; "how do I best handle this as a teaching moment?"; and the essential "pick your battles does not mean pick a fight--especially one you can't win." By all means, instruct--but remember your audience.
My wife's encounter with a Jehovah's Witness at a supermarket comes to mind. When the grandmotherly Witness said "God did not come in the flesh," Heather merely smiled and without a trace of snark or anger said "Yes, He did."