Cormier's ratio was a bit low, but his actual T level was pretty much normal. (EDIT: according to Conte. Assuming we can trust the T and E levels he posted)
With Jon's results, many have focused on the low ratio, but the real question marks come from the low T levels. When you cycle on and start putting synthetic T into your system, your body will stop making natural T because it's no longer needed. Then, when you come off cycle, it takes your body a while to start producing natural T again.
Jon's tests throughout December, even though they're absent of any banned substances, (PED-wise, anyway) have the look of someone who's just recently come off cycle. If his post-fight results show more normal T levels and a more normal ratio, at first glance, that would seem like good news, but it actually wouldn't be. If his T was low in early-mid December and then rebounded a few weeks later, that's a pretty good sign that he was up to something in November.