He is right, the band-aid will bring it around for awhile but as your swing gets better and better, you will have to change your grip again down the line because you will then be hooking it. Everyone here knows how tough grip changes are to make. As for the interlocking grip, that is quite fine (just ask Nicklaus) but the issue is the positioning of that grip on the golf club. I've seen apprentice instructors just wanting to give the student the "immediate" fix take the lower hand and roll it under the club somewhat (strengthened grip) to solve a slice...yes the ball flight will improve temporarily but the problem hasn't been fixed.