Are you sure it's ball and glove must be separate and not just "hands" ?
Most rule sets indicate that the hands must be separated. The ball can be in the hand or the glove.
I was watching a local college showcase tournament this weekend. One pitcher never once put her hands together before the pitch, but the umps never called an illegal pitch. Don't know if they just didn't notice (doubtful) or just didn't care to call it. Seemed strange.