If you record them mono and then pan them to both channels, why not record them stereo?

In a thread some time ago I asked about this, saying that I record my vocals onto 2 channels because I can have a lower gain level (to avoid any kind of clipping) and then have the channel volumes up higher. In that thread I used the logic that 1 = 1, but so does 2 x 1/2 = 1, the theory being that 1 channel recorded hotter should mathematically be the same as 2 channels recorded at half volume but summed (2 x 1/2). On that post you replied that in audio 2 x 1/2 is not the same as 1, but never got into the reasoning why that is true.

Bottom line is that I won't say what I do is technically record the vocals in stereo as much as I record it mono onto 2 tracks and then sum them. I do not have a powerful voice and my vocals, though I record them to the point where the Real Band VU Meters are hitting the red zone, are always was too quiet for the music. And if I turn a single channel up to "11", they start to distort. But 2 channels at 5 1/2 give me the same 11 without either one of them clipping and getting distorted. At least that is my logic.

Scott, why is that logic not correct?

Also note that this technique was born from too many people saying my vocals needed to be further out front when I had no headroom to put them there. Also note that if I have vocals in tracks 7 and 8, they are both panned dead center and I never make one louder than the other. They are direct parallel vocal tracks. Not done for stereo effect, just to have more amplitude there to work with.