I happen to be the owner of this particular flute (even though this is no longer my “main” flute). As I remember it, it was the first model of this kind that Maurice Reviol made (back in 2011). This is similar to the Eb/Bb on the clarinet. Overall, I find that it is most useful for chromatic passages (A A# B / B Bb A), which is probably of very limited interest for ITM. Besides, I find that it makes more sense on the clarinet than on the flute: this is perhaps because the left hand is perpendicular to the instrument on the clarinet, and the fingers are very free to move, whereas it is at an (uncomfortable) angle on the flute. It’s an interesting concept nonetheless, and M. Reviol’s keywork is quite nice.
I think anyone who lost their left thumb would be glad of this set up but it looks cumbersome IMO. I’d be interested to know if it was optional to have the regular Bb key. it looks like a beautiful instrument nevertheless.
Or for the ones that use their left thumb to hold the flute (piper’s grip and the like). I’m trying to learn the standard way of holding the flute, but I still find it easier to hold the flute with my left thumb. This is why I’m interested in this kind of setups.
Yes, I think that in the position shown in the pictures, the lever touch would be in the way of my LH ring finger.
I suppose that a RH lever would be more suitable, like this other ones: