Thread Stereo Delay...perception...how to fix it?

Hey, I have been mixing for over a year and I have run into not so much a problem but an annoyance. I mostly mix hip hop but this could apply to any genre. When I am mixing in background dubs for emphasis on key rhymes or punch lines I like to put a stereo delay on it. It gives the key lines a thick and wide feel. I usually use anywhere from a 5 to 30ms delay between identical tracks panned left and right. Sometimes hard panned but most of the time not, just enough to give it a wider stereo feel. Now my problem is even though the left and right channel of the dub track is balanced power wise, the stereo perception is always dominate on the side that is not delayed. Maybe it is because my ears are hearing the left channel of the vocal dub being played milliseconds before the right channel, I dunno...

Anyways, I have tried different delay amounts but always get that unbalance stereo perception on the dubs. I have used two separate takes of the same dub and panned them out, that seems to work but I lose that real tight feel that a single dub provides.

Let me know if you have experienced this same problem or what you would do differently. How to take a single track of dubs and make it sound wide with a balanced stereo perception....

Thanks
-C