To be accepted into the President's guest worker plan an illegal alien has to have an illegal job, while a legit guest worker applicant has to find an legit employer. The job held by the illegal alien was never available to the law abiding applicant, therefore legalizing them on the basis of entering illegally and working illegally secures for them the advantages they gained by breaking those laws. Illegal aliens would have a head start in the President's guest worker plan because they jumped the line.
The advantage they gained from jumping that first line would carry on as they moved to the green card and citizenship lines.
