Trying to add 2 different specularity layers to the same object, not sure how to do it

Jonstark

I'm trying to put 2 different specularity layers on the same obect, one added to the other so that I can have 2 different specularity effects (one that is low highlight intensity and with a low roughness, to give a large but subtle soft specular effect, and another with a higher highlight intensity and higher roughness, to give a sharper but smaller specular effect).  If highlight and shininess where in the same channel, it would be easy as pie to do this, but because highlight and shininess are in different channels I'm running into a wall.  Is there a way to do this?  Anyone got any ideas?  

Headwax

perhaps try a low intensity blurry reflection in the reflection channel using a map

or similar in glow channel to fake it