Call that passive-aggressivity, social engineering or mind games, I call it just a game. Multitasking at work is tons of fun when you've practiced enough to recognize and leave all error-prone activities out of the picture. And it's very good to make people double-check their problem before they come bother you, even though you're behaving like an open and helpful guy all the time.
P.S. I'll add that if the boss had taken Ed's suggestion, all of this could have happened asynchronously in email or the ticket system. Especially if the user has been given a copy of SnagIt or similar screen capture software on their system (along with strong admonition to never "snag" confidential data) and been shown how to use it.
Screenshots (or these days I suppose, video) go into the ticket. Ed can see it's "really happening". Ed confirms and follows up with Fred. Fred responds the next time he reviews emails or tickets. Ed follows up with the boss.
Time for Sue: ~30 minutes
Time for boss: ~15 minutes
Time for Ed: ~15 minutes
Time for Fred: ~15 minutes
If Fred reviews at least once a day, boss would have his answer latest by mid-day of the following day. As compared to mid-afternoon of the same day while burning a lot of expensive time/resources.
If I'm being strung along like that, knowing that my attention could be required at any minute, it is extremely hard to load a chunk of code in my head because any spare brain-cycles are reflexively spent trying to figure out if my input is required yet.
This is very much like trying to read when you're tired. You'll read 5 pages and then all of a sudden realize you don't even know what you read in the previous paragraph.
Sure you can triage your mail and small tasks and quickly do the stuff that takes 3 or 4 minutes, but I find that I often have just a few of those tasks. Certainly not enough to fill 3 hours worth of time.