As in the title;

Not so long ago, I started blending test thru commercial esp machine, thus I moved from 'cinnamon' roast to near 'french' to better optimize body and its character.

I didn't pay so much attention on this because I had no chance at all then. I saw a thread explaining that overheat is the usual suspect.

That said, I wanted to manage enough heat momentum to develop the beans but not as much as the crater cracks. But this was not easy.

How often do you guys have this when roasting?

In my personal experience, low heat during the ramping phase revealed some spicy fragrance in grind or as if sour element didn't well participate in the reaction. This was obviously outstanding during extraction, even aging couldn't help this out.

Hope you guys share me your experience:)