Some times it is really really nice to be able to comment out a line of code.
It is a small thing, but when trying to debug an issue you some times have several lines of code that output stuff to e.g. the chat.
When you're done (for the time being) these lines need to be removed.
It can be done, but it is often a bother, in contract to just placing a // or # or whatever is used in the language of choice.
It would be so nice to be able to something like this in MTScript.