The next workout was today: 5 x 1200 m at 5K pace. I determined that considering a 5:50 5K pace, I would have to run 1200's in 4:21. At then end my splits were 4:23, 4:15, 4:19, 4:19, 4:16 (rounded) for an average of 4:18.33. All this without ever feeling oxygen debt or pain.

As for discomfort, and a bit of burnout: yes. When I started my last interval, at around 300 m into the fast run (so 900 m left), I thought: "This is not fun. In fact I'm fed up. I really want to quit now." But of course I didn't.

So it does look like I'm in pretty good shape. I'm wondering if I could break my shorter distance PRs. Also, it is very temping to attempt ton go out faster than 3-hour pace. (Which I will not.)