Never heard of it. The charging circuity is built into the iPhone, not the power adapter so the maximum charging rate is designated by the phone itself, regardless of the adapter you use. Pretty sure the max for the iPhone is 2.1 amps, which would be the 10w adapter which is what I use. It definitely charges faster than the 5w charger that ships with the phone, but it certainly takes longer than 5 minutes to charge fully.
And I'm not talking about you, I was more referring to the people that actually tried it and nuked their phones. There's been quite a few, just google "Apple Wave". Pretty sure it's the same group of people that thought iOS 7 made their phones waterproof this time last year lol.