to go for a vincent actually means go take a piss.
the phrase comes from a Quentin Tarantino film
PULP FICTION, in which the
character named Vincent
Vega (starring John Travolta), is always "oh so desperate" to use the bathroom facilities all the time.
Vincent: ...so not only i shot that
guy in the face, i have a very bad luck walking out of the toilets...
never consider to go for a Vincent, unless you expect something catastrophic to happen
later...