Snarky Puppy's about page (with profiles of the artists) says this about guitarist Mark Lettieri:
Mark Lettieri is a guitarist, composer and sometimes producer residing in Fort Worth, TX. Lettieri works both on stage and in the studio with numerous artists and bands on local, national and international levels. He also writes and records instrumental guitar music under his own name. Mark joined Snarky Puppy in 2009 as a stunt guitarist, and the band has kept him around since, despite his growing collection of Van Halen t-shirts.
What does this mean? Does a stunt guitarist specialise in stage dives and setting instruments on fire, or am I missing some terminology?