In a word..no. The Kernel for ICS is distinctly different from that of Gingerbread. Until either Motorola unlocks the bootloader or they issue a signed version of the Gingerbread with Kernel for direct flashing, we're stuck in ICS land and never to return to Gingerbread.
Now on to the power issue. First, you should do a Factory Data Reset. When upgrading between Gingerbread and ICS, there can be unresolved issues that cause battery drain.
Once you've done a FDR, then you should go through a meter training:
Power the phone off.
Plug in the charger supplied with the phone and allow it to boot into charge only mode.
Let the phone charge until it reaches 100% (to check progress along the way, tap either volume up or down briefly).
Power the phone on and use it until it warns of a "Low battery", at 10%.
Power the phone off again and repeat the charge to 100%.
After the meter training, you should be good to go. There may be other changes you might wish to do such as reducing screen timeout, reducing screen brightness, turning off 4G LTE (if you are in a poorly covered or non-covered area), using WIFI whenever possible, and a host of other tweaks or methods of extending battery, but to put the wraps on this, I am running ICS V .215 (and you would probably also benefit from that upgrade), and I have to charge only ever two days.
To upgrade to .215, go to
http://www.droidforums.net/forum/droid-razr-support/217843-mattyps-215-leak-classroom.html and get acquainted. The instructions for the upgrade and links to the files are there for your convenience.
