The resistor was a quick fix to the original EHC's used in the new models when they came out in 05. If you still have the original EHC then DON'T remove it! Once you get the updated EHC you can pull that out. They didn't do it when mine was replaced (mechanic shattered some lights) and I email BDM about it and they said I could pull it but didn't need to. I pulled it out anyway.
With the original 05 EHC's there was a chance that a spike or to much voltage (or something like that) could cause your EHC to melt down. This was the fix till they updated the EHC's. I know because mine melted down on the side of the freeway back in 05.