Bracketing trick, double exposures one touch

If you shoot brackets on a tripod with a release, do your metering and find your highlight and shadow exposures.
Set an exposure for your first bracket in manual mode, mine will cover 3 exp at 2EV. Set your exposure compensation to spread the bracket enough to cover the other end (+or-). After shooting your first bracket, turn your mode dial from M to A. Shoot another bracket. My D70 will cover +5, +3, +1, 0, -2, -4 or equivalent by setting +/-5 on exposure compensation. At +/-3 I'd get +4, +2, +1, 0, -1, -3 or equivalent.

Could you be a bit more specific on this technique. i can't figure out what you are doing.
Buzz

I had tried this on my own, but it is much clearer in PRACTICAL HDRI book.
You can set your normal bracket on Manual. I get 3 shots at 2EV. If you spotmeter to establish your max/min exposures, what EV range do you need to cover?
Then turn your shooting mode to Aperture priority. If you were at correct exposure before, nothing should change. If I compose so my meter is 2 stops off in Manual, Aperture should shift me two stops to compensate.
If I set my exposure compensation to my max +/-5, I can cover a metered range of 9EV, plus whatever range I have above or below metered in my cameras normal DR, about 3.5EV. So I have something less than 16EV to work with under ideal conditions.
If I only use 2 or 4 comp, I will repeat exposures. If I use 3, I have 4exp at 1EV and 2EV at either extreme. 5comp gives 2 brackets of 2EV separated by 1EV.
If I compose so