I came back from a couple of conferences not long ago. Here is something non-mathematical that I learned, which changed my opinion regarding the title. What I learned can be described by the following exact sequence:
$latex 0 rightarrow I rightarrow T rightarrow C rightarrow 0 $
Here, $latex I$ represents an Israeli speaker, $latex T$ represents the talk, into which the Israeli speaker injects all his knowledge into, and $latex C$ represents a mostly Chinese audience, onto which the talk is mapped surjectively. Unfortunately, the kernel of the map from $latex T$ to $latex C$ is precisely the image of the map from $latex I$ to $latex T$, so really all that the audience is left with at the end is everything in the talk modulo what the speaker was trying to say.
Paul Erdos is known for saying that the international language of Mathematics is broken English. It is true that the broken English spoken by a Hungarian, a Russian, or an Israeli are almost the same language. But there are other countries where a very different dialect of broken English is spoken. An Israeli breaks English in directions orthogonal to the way a Chinese would.
Corollary: The next time that I go to China (if they ever invite me again!!) I will prepare a presentation.
Besides the fact that I gave a talk that I thought was incomprehensible to many people, the conference was very interesting, and I met great people, and received the finest hospitality I ever did.
Interesting and funny, but somewhat too much vague/diplomatic sophisticated. Perhaps it is possible to describe the contents of the post in a more direct way so that, in particular, it will be clearer why giving a presentation in China is a reasonable corollary? Usually I prefer to give a presentation for various reasons, among them:
1.It is easier to estimate the needed required time. This really works(!), assuming one is not tempted to put too much material in the presentation. I have seen so many people, even very famous ones, running out of time when giving a blackboard talk. It seems that such running out of time is the common case (but I admit that this is not always the case and there were many talks without this problem).
2. One can save a lot of time in the talk itself since most of the information is in the presentation (but the preparation can take a lot of time).
3. Once the presentation is finished, it can be easily archived and become accessible to other people (e.g., by putting it in one own website).
4. Information from the presentation can be easily copied to other presentations in case of need.
Responses from other readers/writers (in particular from supporters of blackboard talks) are welcome!