We've been through this so many times before in this thread; it's easier for me to just quote G&M again: "In view of the value for Earth [stopping distance of mBH's] 3 × 10¹¹ cm, these [stopping] mechanisms [in Earth] cannot efficiently slow down neutral C[osmic]R[ay]-produced black holes in Earth, or in other bodies such as planets and ordinary stars." (p. 33)

I agree that my choice of parameters is "fine-tuned", but they are taken from the allowable parameter space. You might be right that it's more likely that we live in 10 dimensions rather than 6 dimensions, based on a priori considerations. However, such a priori considerations cannot rule out a 6-D (or 5-D) world, and there certainly is no experimental data that can rule out 6-D scenarios. The mere fact that 6-D scenarios might be unlikely compared to 10 or 11-D scenarios doesn't really affect my argument: or rather it would if all we were talking about was a $100 bet on the outcome of an experiment. In the present case, we're betting the planet. "Unlikely" isn't good enough. We need reasonable certainty (a term I thought I had coined, but I see that Plaga uses it as well) that Earth-swallowing scenarios cannot occur.