I still don't get why it should be dangerous, and since that rule exists for C++ already you have to configure your editor anyway, so I don't see the problem. If you have an example where the C++ rule would be dangerous please show it.
The danger comes from the editors. There are times that you do not know what an editor will put, tab or space, so it is safer to always use space. For example, if you use vi to edit a .py file with spaces, and allow it to indent for you (without expandtab flag on), it will most likely use tab for indent. The source code will look right, but fail to run. The other case around is also valid. With vi, you can at least configure it, this is not the case for other less capable editors. Bo
