memory shortages

At Do It With Drupal last December in New Orleans, I was very rude to the inestimable Matt Westgate by making a contradictory comment in his "Drupal under Pressure" high-performance session about how APC decreases rather than increases total memory utilization in Apache with mod_php and then having my phone ring with an emergency client call and having to walk out of the room without explaining what I meant. Poor form to say the least.