Ask HN: Suggestions to non-English-native speakers for presentations?

Last week, my manager asked me to rehearse my presentation (a workshop talk). It was fine, but I got a comment at a slide, which showed only commands and screenshot and I explained the details.

The comment was something like, "Add more texts as explanation, not just speak them. We are not native speakers. People may not understand our English or just get distracted, so leave more information for them."

Non-native speakers DO distract people, at least me. People I met in conferences are often too kind to mention this, or they just don't feel the same way as I do? Consonant, accent, grammar errors, ... any weird combination of them can distract people, or am I just not focused enough?

Back to the strategy against distraction. I don't think being verbose is acceptable because it causes distraction by itself. Even worse, sometimes the speaker just gives up, reducing him/herself into a slide player. Looking at someone who plainly speaks out all the words on the screen for over ten minutes is such a painful experience, but it occurs much more often than listening to a good talk that I can resonance with.

So dear hackers, I am curious how you feel when you listen to presentations from non-native speakers. The most impressive/worst presentations you remember, what were your thoughts, did they affect the will to make connections with those people, etc. Among all the interesting questions, the more important one is, what are your suggestions to non-native speakers to prepare for their presentations? Or do you think that it has nothing to do with native or not, just depends on speakers' preparation/effort?

Disclaimer: Experiences are subjective things. All answers are highly appreciated, especially politically incorrect ones, because I know what I really think inside my mind every time I say "Wow! You speak Mandarin so well!"