For my recommended pen nib (the Speedball B-5) and either of my recommended inks (Rapidograph 3084-F or Reeves and Poole), the drying time appears to be 5 minutes. In these tests I first wrote, and then wiped left-to-right after the marked delay. Both were fine after 5 minutes.
The Reeves and Poole 30 minute smear was caused by a dragged fingernail during the 1-minute swipe.