So far I've had mixed results. Part of that may be an unfair test: I've played hockey twice this week, Monday and Thursday nights, both with 10:15 pm ice times. I'm so amped up after playing that sleep doesn't usually come until after 3 am. So I took melatonin, a 3 mg dose, on the way home from the rink, hoping it would kick in by the time I got in bed, but I didn't get to sleep until 3:30 both nights. On top of that, I brought a post workout drink with me both times, and found that it contains glutamine, which definitely has a stimulant effect on me.
Today I started my night shift run, so I went down for a nap about noon, after getting a truckload of mulch from the landscape yard and cutting the grass this morning. I took a double dose (6mg) of melatonin shortly before going to bed and slept like the dead for 3 and a half hours. When my alarm went off, I was sleeping so deeply that I couldn't mentally process the clock showing 3:30 (my normal wakeup time for day shift) and sunlight around the edges of the curtains...... So today it helped me for sure. I'll take a double dose again in the morning before bed and see how I sleep. Usually the first day's sleep isn't so good, so if I sleep well, this should show the melatonin helping me.