I was taking a look at this question and used the current URL as a quick test, this gives an actual ASP.Net error page:
https://stackoverflow.com/questions/3541426.
And this gives an empty page (0 content length):
https://stackoverflow.com/questions/3541426..
The same happens if the title is included as well., this works:
https://stackoverflow.com/questions/3541426/title
ASP.Net Error Page:
https://stackoverflow.com/questions/3541426/title.
Empty response:
https://stackoverflow.com/questions/3541426/title..
I'm not sure what the desired behavior is here, but it seems like a 404 for the non-matching routes would be the appropriate page, just to keep things consistent. I agree this is a very minor issue with no real consequences, just pointing it out in case someone's digging around in the routes later and wants to make this match.
