Easily communicated in a "ceteris paribus, having communicated my evidence across teh internets, if you had the same priors I do, just by you reading my description of the evidence you'd update similarly as I did when perceiving the evidence first hand", yea that would be a tall order.

However, all evidence can at least be broadly categorized / circumscribed.

Consider: "I have strong evidence for my opinion which I do not present, since I cannot easily communicate it over a forum anyways" would be a copout, in that same sentence (119 characters) one could have said "My strong evidence partly consists of a perception of divine influence, when I felt the truth rather than deduced it." (117 letters) - or whatever else may be the case. That would have informed the readers greatly, and appropriately steered the rest of the conversation.

If someone had a P=NP proof / a "sophisticated" (tm) qualia theory, he probably wouldn't fully present it in a comment. However, there is a lot that could be said meaningfully (an abstract, a sketch, concepts drawn upon), which would inform the conversation and move it along constructively.

"What strong evidence do you already posses (sic) that leads you to believe this thing" is a valid question, and generally deserves at least a pointer as an answer, even when a high fidelity reproduction of the evidence qua fora isn't feasible.

Yes there are two senses. I meant "a". If ibidem has some bayesian evidence, good for him. If it's not communicable across the internet (perhaps it's divine revelation), that's no problem, because we aren't here to convert each other.