I do not think anyone was accusing you of that. Nor do i think anyone is accusing you of anything nefarious. I know I am not. I think it's more of "biting more than you can chew" and your pride preventing you from admitting it, even to yourself.

With all due respect, sir, I think the phrase you were looking for is sorry. After four years of leading your customers down the garden path, you are in no position to offend them. Even if they are complete idiots and completely wrong and you are completely right, you are still obliged to apologise and explain any misunderstanding from the position of humility. Using phrases like "your post is particularly incoherent" can be seen as a sign of arrogance which is rather unbecoming in your position.