>> A transformer won't pass DC.
> under normal operating conditions.
I stick to my claim. Transformers don't pass DC. (Unless they have gone bad, interwinding short; unlikely but not impossible.)
Transformers pass THUMPS. The damage, if any, is done in around 10 milliSeconds. By definition, the bottom of the audio band. (Because the transformer passes audio, but not sub-audio. The exact definition of "audio" is up to the transformer designer, but "DC" is not a possibility.)
> According to Royer; ...a serious voltage spike can blow the ribbon...
Note: Royer's word "spike", not "DC". Spike, thump, call it what you will: it is both. I'll sketch some pictures to show. I feel that the "thump" aspect is what blows the ribbon. Royer is mostly trying to stop you from having Phantom accidents, and "spike" may be more frightening which is what he wants. But since we may already have had a Phantom accident, I think it is important to see what really happens, to clarify diagnosis and possible preventions.
> according to Eddie Ciletti in Mix Magazine; "...phantom power is invisible to dynamic and ribbon mics. However, if pin-1 and pin-2 (or pin-1 and pin-3) are reversed ?...? 48 volts would be applied either across the mic's transformer or across the capsule itself."
Here it is possible to confuse dynamic with ribbon. Many dynamics have no transformer, so the balanced (or UN-balanced) Phantom is applied across the capsule. Some dynamics and all ribbons have a transformer: the transformer is subject to 48V DC, but what passes to the capsule is audio band only.
Look, I need to get to bed but will return to this when I can draw you a picture. Meantime, it might be helpful if someone has pix of a low-Z transformer passing square waves of 20Hz and 20KHz. From pix of normal transformer action, we can derive what happens in the normal and abnormal Phantom situations.
BTW: all this makes me think ribbon mikes SHOULD all "be Phantom". Not that they really need the first amplifier stage moved up into the mike, but because having a phantom power stage inside the case isolates the ribbon from the now ubiquitous always-on Phantom supply.