pschoonveld was a real user, and not a part of BlockStackers, so far as I am aware; he answered a question from CmdrTaco on December 2nd, 1999.

As discussed in more detail at Re: The First Ten Perl Monks, it seems that the mysterious pschoonveld, though not officially employed by BlockStackers, was a PerlMonks "insider", a Hope College buddy of vroom, who hung out on the early PerlMonks web site before it opened to the public on 23 Dec 1999.

CmdrTaco, another Hope College student and PerlMonks insider, is the famous Rob Malda, co-founder of Slashdot.