England have impressed running in ten tries against Wales and Italy while Marc Lievremont's France are under pressure after an unconvincing performance in Dublin.
And while Johnson has been impressed with the performance of his back row so far, he made no secret of the impact a fully fit Moody could have on the side against a French back row boasting Thierry Dusautoir and Imanol Harinordoquy.
However Johnson insisted Moody, who made his comeback with a cameo appearance of the bench for Bath this weekend, would only play a part if he was 100 per cent.
"We would love him to be fit and fully raring to go for a Test match," said Johnson.
"It would be great if he is fit to go but if not the other guys have been playing very well.
"There's probably a little bit of a difference between playing 20 minutes in the Premiership and playing against France.
"He will know if he is right or if he is not right - and he'll be honest with us and the team."