Delta Islands without bitmaps?

I am having a hard time trying to get delta islands to work as I expect. I would like to treat each head as an island of its own, but I do not seem able to do this. From reading the code, I believe that I am not able to make this work because the feature ignores objects which are not covered by bitmaps and refuses to put them in their own island? I don't see anything in the docs hinting at this, so I wanted to confirm whether my reading of the code was accurate, and to maybe get some clarification as to why this was done?

Perhaps this would work if I could force every head to have an associated bitmap, but there doesn't seem to be a way to do this? Is there some other way I can force all heads to be in their own individual island?

Thanks,

-Martin