I don't think this is going to be that helpful - their ability to right themselves is partly determined by where they flip and how tired they are already. One successful righting isn't going to mean much (beyond a stressed tortoise).
I'm quite aware of that. But at least if you witness it - you will know your tortoise can. That is good to know. I wouldn't be too concerned about the stress level doing it once - as long you're not flipping him for fun on a regular basis.
And...as Linhdan and WithLisa pointed out...they right themselves regardless. It might also point out some trouble spots in the enclosure where it may become difficult to right themselves that maybe can be addressed.