People are asking me about DTR again (because pretty much every competing program displays it now) and it's still about the worst idea in coffee roasting (if you're using it, I can guarantee that your roasts have less batch to batch consistency than they'd have if you just stuck to the raw duration values instead of obscuring those with a division operation that doesn't correspond to any known chemistry). If you want it in Typica, I need an argument that outweighs the damage this concept causes.