Is pointing out that an instructor is wrong a sign of disrespect?

If your doing something wrong your teacher should correct you and for them you telling them they may be doing something wrong is improving them as well. And if your paying for lessons, you should be aloud to ask questions and question things. Make sure you get your moneys worth.

But there is a line you can't cross between being intrigued and puzzled and then humiliating someone

Several thoughts... First, Inosanto has earned his respect. If you were someone as well known as Inosanto and spoke out, then it would be considered wrong. Being that you are not well known, it looks even worse to others. I don't know what or where you made these comments, or how you stated them. It could be what you sai8d or how you said it. OR it could be where you said it. I have never seen anything that would make me believe that FMA had any influence on Western boxing either. I've been involved in fighting arts a long time and this is the first time I have heard of any claim that FMA had anything to do with boxing. Did Inosanto really come out and say that FMA influenced Western boxing? If so did he give any evidence?

Edit: It appears that FMA might actually have had some influence on Western boxing. A Bing search on the terms Filipino martial arts influenced boxing brought up a number of hits. One is... http://ito.inayan-eskrima.biz/Filipino%20Boxing%20...