Short answer is yes!
Since posting above a couple of years ago I’ve switched away from ISM on my outdoor road bikes, on the advice of a bike fitter. Have found I’m more stable on a traditional saddle with a cutout. Noticeable improvement in little things like riding no hands, getting a gilet on or off while riding, fuelling in the middle of a race, putting a hand on a team-mates shoulder or hip to let them know I’m there, etc. Could do all those things previously, they’re just easier now.
Think the issue with the ISM is that it really only worked well for me in one position, which was perched on the nose with my sit bones on the prongs. It was great in that position, and made it very comfortable putting out power in the drops or aero hoods position, but I never really sat that saddle in any other way, as scooting further back on it was uncomfortable due to the nose width. That one position wasn’t particularly stable, partly because my weight was forward in an aero position, and partly because those prongs don’t offer much stability. Whereas on a traditional shaped saddle I can still get forward and aero when I need to (though it’s a bit less comfortable), but I can also shift back on the saddle comfortably which has 2 benefits in terms of stability - less weight on the front end, and also the saddle cups my sit bones in that position so I have much more contact area with the saddle with which to control the bike. Think the ISM is a great saddle for TTing or tri where you want to be forwards and aero all the time, and also a good indoor option where it’s very comfortable and you don’t need to worry about stability (unless you’re on rollers!). Don’t think I would use one again for all round road racing and riding though.