I've always thought the reason for particularly hot peppers was dry weather after the growth period which requires a ton of water. Sort of like getting really flavorful tomatoes. Get them nice and big from all the water, then let them dehydrate on the vine. This would explain why mine, and so may others around me had such hot peppers this year.
But, I have had differences between peppers on the same plant. so what do I know.
Bought 16 heads of garlic at the market today to plant. Varieties were Asian Tempest, Translyvanian, and Kilareney Red. I also got various peppers on the cheap to make some more hot sauces. Ancho, poblano, ghost, lemon, and other habaneros. Since I can't brew at the moment (tore something in my knee), I need to brew something!
I've also been putting down black mulch to kill the grass off, so that I can triple the size of the garden next year. Pulling the tomatoes today. Always a sad time for me.