OK having got that off my chest, I do rather agree with Jack's last point.

If you are going to play the bass recorder, it is better in the long run to learn to read from the bass clef because you don't then have to go through all the rigmarole you described.

I can, and do sometimes, play my bass (and contrabass) recorder from treble clef reading it as an F alto (including reading up an octave), but I am really much more comfortable playing from bass clef.