I don't think an HBa1c of 5% (30 ish) would "lead to" hypos. It is an indication of possible hypos, probable hypos even, when looking at Type 1s as a population. But looking at you as an individual, if you are achieving 5%, and you are not having hypos or skating close to them, then the near normal HBa1c is not going to cause you to have hypos.
Another way of looking at it is this. If you have an HBa1c of 5% and erratic blood glucose, you are definitely having hypos. If you have an HBa1c of 5% and stable blood glucose, you are not having hypos. Because HBa1c measures an average, but doesn't measure whether blood sugar is stable or erratic, the HCPs have to treat low HBa1c as a reason to investigate in case blood sugar is erratic, in which case low HBa1c will be an indicator of hypos. But low HBa1c does not necessarily mean hypos.