Remember, IRC and mIRC are used by many users who are not technical. They should not have to understand how IRC works in order to use it. Even a technically-aware user would have difficulty if they tried to use IRC for the first time and received cryptic connection errors. Most users would likely just give up.
So, no, I will not simply remove the restriction.
Whilst I can quite understand the wish not to confuse non-technical users, it seems to me that restricting this to 10-chars might not be the only solution.
For example, would it be possible to allow unlimited characters, but if the user has used more than 10 characters then to watch for the error message that happens if the server doesn't support this and provide additional error message text advising that the probable cause is that the server only allows 10-characters?
If this is possible, then mIRC would not need to cater to the lowest common denominator functionality.
