Not particularly solving your question, but I wanted to comment on something.
Theoretically, this might sound fine, but in reality, fan speed isn’t that reliable. For example, in some cases it’s not regulated, at all, as it always runs at full speed. In other cases, it might not work correctly, so perhaps it’s not fast enough.
Perhaps it works fine in your case, I don’t know that, but generally I wouldn’t trust fan speed alone too much.