i always scrape out the seeds, which inevitably removes most of the placenta/pith, so i mix in some hot sauce/paste into the filling.saves me howking seeds out of my teeth & gives a reasonable heat level.
might even make some for christmas dinner!!!
If you take the time and remove only the seeds or reimplant the placenta in the stuffing no heat will be lost. Removing the seeds offers a lot more space for the stuffing. That's why I do it.