Normal on certain guns as described. I shoot both an XD and CZ that do it during competitions and it's quite the nice 'feature' for increasing reload speed. Which is where ALL shooter loose their time.
Safety-wise it's a non-issue.
The only slightly encountered negative would be robbing the slide of that extra momentium from racking the slide manually. Not an issue 99.5% of the time, but if the chamber is a bit too dirty you might not have the slide fully go into battery.
FWIW, you should not be using the slide release anyway. Reach over and grab the slide with your weak hand, pull it all the way back and let it go. In a stress situation (high-speed competition or self defense) the first thing you loose is fine motor skills. Like finding that little lever with your thumb and not slipping off of it.