So I completed the weeks data (and no I swear I didn't make this up). Monday ~37 Adventures - 2 Legendaries Tuesday ~35 Adventures - 1 Legendaries By my math that makes 225 adventures and 9 legendaries or 1 legendary per 25 adventures. This includes the treasure club, and I also hit the loot fairy twice on most of these day ( I didn't do it on the Black Plume day at all). I didn't touch MP this week.
I think you should separate the loot fairy from the rest. I wasn't counting the loot fairy when I posted the data, because it's a different thing (although it's also SP). How many of those 9 legendaries where with the Loot Fairy? My data today, excluding the Loot Fairy: 33 adventures, 1 legendary (treasure)
Hmm. I don't think I've ever done that well. My latest track is about 1 per 100. I guess if I'm below average I'll just have to farm more.