Pocho como Estereotipo...

Fronteras y representaciones sociales: La figura del pocho como estereotipo del chicano

"JMV Arce - Aztlán: A Journal of Chicano Studies, 2004 - UCLA
Las representaciones sociales son construcciones colectivas a través de las cuales se construyen
a los otros(as) generalizados y se producen explicaciones de sus rasgos y
comportamientos. Las representaciones sociales, de acuerdo con Jodelet, son ..."

A good article that looks at the perceived transgressions of the 'pocho' by Mexico-born persons. It points out the tie to language and call, "No te apoches" with regard to the language.

 I really don't know the origins of this picture except that I found it on wax.fm, but I would say there is some stereotypical connotations of the style that this guy is putting out there.

If you have access to JSTOR through your university library, I would recommend finding this article that way.