Help with parallel distortion

[propman]

Long ago, in a land far, far away, Kanye West put out an album called 808s & Heartbreak.
At one point, he released the stems for the track Love Lockdown to be remixed by fans.
While not really in-line with my regular choice genres (though I somewhat dislike genres),
I dug the album and downloaded the stems. As I recall, the producers implemented this technique.
One track dry vocals, second track distorted vocals.

That sticks out in my mind because it seemed so strange to me at the time.
Something just occurred to me, though. Sure, you have wet/dry controlls... but what if you want to affect the distorted signal further?
It wouldn't be possible to do so in a chain without affecting the dry signal as well, 'ew see.

[mindsound]

To those who questions the use of parallel distortion, it is in fact very useful.

The main reason is that any distortion unit will also change the tone of your track (not always in the way you want). So you use parallel dist. to keep the "original" tone of your track while adding distortion to it with a duplicate track. Bass tracks, as Rami talked of, is a very good example. In fact, put a bass track through a dist. unit (or plugin) and for sure, you'll lose in the bottom end. But if you duplicate your bass track, cut the bottom on this new track and distort it, you'll still get the bottom of your source track mixed with the added texture of your duplicate (distorted) track. So, you don't lose anything. You just gain more texture (which is a great trick to make a track cutting through a busy mix btw).

[propman]

I've heard this effect being used (and used it myself) on acoustic guitar a number of times too.
I really like the way that sounds.

[MrWrenchey]

I think Jon Foreman used parallel distortion on his vocals during the chorus of Switchfoot's song "The War Inside."
I may be wrong, but it sounds a lot like that's what he's doing.