is it possible that a wrist strap can change your groups. i switched to a strap and it seems everything has changed. is it a psych deal or what...............

There`s a good chance that switching to a strap will change your point of impact. You release and hold your draw different, I even change when using different wrist strap releases.

I can tell you from experience that going to a wrist sling will definately improve your shooting because you will tremendously reduce the amount of torque you put on a bow because the sling allows you to shoot with an open hand without having to be concerned about dropping your bow.

This may be very obvious to others, but be sure that your wrist strap is not tight on your bow hand. You want it to catch you bow if you drop it, not hold it in place. When I first started shooting with a wrist strap I had it too tight.