A battery pull is hard reset which means it terminates all running processes on your phone. A soft reset does not. Therefore, the two will boot up with different amounts of memory with a hard reset giving you more.
And a third different memory reading you will get (as i found out) is when you install a new os it will be even higher than after a hard battery pull, being all apps have been completly shut off, which is why some ask for permission to change settings, while some apps hold your information after a battery pull like Viigo, Vlingo Weatherbug, after a update that information is not stored on the device anymore and you have to reenter all the passwords and user names thus higher memory.
Yeah I understand the difference between the two resets, what I am getting at is if I soft reset it twice, I boot with different memory each time... Same with a batt pull.. Do it two times different number, never constant