The IPSC fraternity would know in detail. Such a mounting would place it a bit high over the bore axis, muzzle flip and holes in the target lower than sighted as close distances, the same as for scoped rifles. If you shoot only occasionally with an optic on your handgun it should work fine for many years. For close up shooting at centre of body mass in low light it works excellently.

Production optic division in IPSC started that way, with mounting plates in the rear sight dovetail. Machining the slide to fit the mounting plate is standard today.