As for this thread. My opinion is that WC does contain stand-up grappling. As in Kum Na/Chi Na. But it's a grappling that is alive and flowing by utilizing what we refer to as CONTACT CONTROL, and not actual dead hand fully committed grappling.
This is the core difference between anti-grappling, and counter grappling.
For more info read:
http://www.hfy108.com/forums/showthread.php?t=2346
As for mixing in grappling with WC. I believe you can mix in whatever you like. Once you understand WC's core body mechanics, to varying degrees, any outside technique and applications can be incorporated successfully.
However I do not think I'd ever go to a WC school that is trying also to be a MMA school to learn Jiu Jitsu. I'd rather just go straight to the source and learn the real deal. But hey... that's just me.