- HMBIA Authenticity Committee:
The question here is what can we call a “source?” For example, many call a source some pictures depicting elements of armor, ignoring the fact that they belong to the XXI-st century and have nothing to do with history. Ideally, the most credible source is an artifact kept in a museum. You can look at it, take a picture. Having such evidence no one will be able to say that some thing did not exist.
However, an issue of detail compliance might arise here. For example, did a helmet have an aventail? And if yes, how was it attached? There are situations when a part of a helmet is lost and it is not clear whether there was an aventail or not, and they are a reason for an ongoing debate among reenactors.
On the second place in terms of credibility level are bas-reliefs, statues and engravings. If you refer to the latter source, then, as it has been mentioned before, you’ll need to find at least two pieces of evidence (i.e. two engravings).
Questionable elements of armor also lead to debates, for example “wolf ribs” visor, as only two engravings survived. We can say that such thing could be in use, but we can’t be 100% sure. Such disputes, in their essence, are eternal, and are an integral part of the HMB movement.