You are being absurdly pedantic. For example >A "range from 0.10 to 0.30σ" doesn't make sense. Out loud, you might read it as "oh point one to oh point three

You are being absurdly pedantic. For example >A "range from 0.10 to 0.30σ" doesn't make sense. Out loud, you might read it as "oh point one to oh point three sigma." And it's fine. Ever written a phrase like "it's very expensive, costing somewhere around $3-4M" with one "$" and one "M" but two numbers?