We have made some custom modifications to the recsum.htm, and yes if you make any changes to the recsum.htm, you will need to redeploy the bpm.ear.
To create a new bpm.ear that incudes the recsum.htm:
If you do not redeploy, your modifications will not show in the approval inbasket, and remember, everytime you do a portal upgrade, and a new set of .ear files are delivered, you will have to add the rucsum.htm to the new bpm.ear. Good luck..
I ended up changing it in the exec folder in the BPM.ear/war. Yes I know that's probably not the 'correct' way to do it, but it seems to work.
-R