In the following MS document page, for the RedirectPermanent method, default value seems to be true instead of false. I have tested it on my local machine and it is ending the response by default similar to Redirect method.

https://learn.microsoft.com/en-us/dotnet/api/system.web.httpresponse.redirectpermanent?view=netframework-4.8.1#system-web-httpresponse-redirectpermanent(system-string)

RedirectPermanent(String, Boolean)
true to terminate the response; otherwise false. The default is false.

Also, it requires to correct method documentation which show up in Visual Studio.