"What size air compressor is necessary?" was dead first in 2005, revived a year later.. Jeremy123 responded at 3:18 am.
"Air Compressor Quick Connector " was dead in 2007. Jeremy123 responded at 2:45am.
"Compressor CFM - HELP!" was dead in 2007. Jeremy123 responded at 2:55 am.
See the pattern?
Also, GarySwart responded to all 3 threads. Mini-coincident pattern.
No split personalities, just people responded to other people who likely haven't been on the site for 2+ years.
Another thing. http://terrylove.com/forums/showthread.php?t=16619 "loud noise and leaky pipes" which has been dead for almost two years was responded to at 3:01 by..............................none other than Jeremy123.
Spam. Every response has a link or two to some lawn aerator site.