Quasi-science at Home: Hotness of Chilli Seeds
So in the interest of science and advencement of human knowledge, I decided to experiment myself.
First, I bought a few Bulgarian Carrot chillies - the shop had no good Scotch Bonnet left, and I like the look of this other variety. They are very hot but not as scorching as the Habanero and relatives.
So I sliced one chilli in half lengthwise and carefully extracted the seeds - wearing latex gloves. Then I wiped the seeds with a paper towel; washed them thoroughly in a fine-mesh colander using a drop of dish detergent to remove all capsaicin from the seed surface. Finally, I rinsed the seeds and patted them dry.
The core of the experiment was to actually taste the seeds. I tasted 4 taken randomly from the heap I obtained; I first mulled them around my mouth and then crushed the seeds with my teeth. They had no noticeable pungency.
For comparison, I also tasted a small piece of the fruit wall, taken roughly from the middle: it was definitely hot. A piece of the placenta instead tasted very hot.
Conclusion: chilli seeds do not add any noticeable hotness.