Having started something like my 28th character on monday I have finally got around to triggering Mirmulnir to attack the watch tower. Every time, out of all combinations of getting the dragonstone, I have never had this happen (getting the stone before getting to Whiterun, with and without knowing about the claw from Lucan, getting it after going to Whiterun before and after knowing about the claw from Lucan).

Every time I have turned in this quest it has always just been Farengar in his room by himself, he takes the stone and then Iraleth interrupts us.
However this time, when I got to Dragonsreach Delphine was there chatting with Farengar about some sort of text she had brought to him, they had a short conversation about the text and then he turns to me and introduces us, stating that Delphine was the one who told him about the dragonstone.

Is there a specially way to trigger this? It's never in any single playthrough that I have started happened in the past. However in saying that not all of them have triggered the Dovahkiin questline.

For reference my the general outline of my story so far has been.

Follow Imperial in Helgen. Split up on exit but meet him at Riverwood.
Kill the giants with the Companions, join them, do the first Whiterun quest for them followed by first main quest for them. Got a quest to kill a wolf in Falkreath.
Went to dragonreach, told Balgruuf of the dragon attack, told to retrieve the dragonstone.
Purchased horse, headed to the watch tower path that crosses back to the Falkreath side of the map from the mountains south of Whiterun.
Cleared Bleakfalls Barrow, circled around the lake to Half-Moon Mill to take care of the wolf for Companions.
Followed a path and ended up at Cracked Tusk keep, got my hands on a piece of Marune's Razor.
Headed to Falkreath, got Hircine's cursed ring from Sinding.
Headed to Riverwood via Helgen, noted no Bandit activity (lvl 10?), through the mine near Riverwood and arrived in town at night looking for a bed to sleep in.
Get to the Inn and Orgnar states that the Innkeeper is out when I try to ask for a bed. Tells me I can sleep on a table if I felt like it (lol).
Legged it to Whiterun, dispatched a vampire that some Vigilants were attacking.
Slept at the Bannered Mare, turned in companions quest and triggered next main companion quest (The Silver Hand)
When to Dragonsreach and above happened.


Literally everything I have done since starting the game. Anyone have any clues as to what actually triggered the Delphine event at Dragonsreach? Its the first time I have had the dialogue from Orgnar also. Is it triggered by going to the Inn there first and being told that she is away? Or something else I did.

I know its probably old stuff but I was pretty excited by this as it was something new (sitting through the same old story gets old after a year lol).

http://www.uesp.net/wiki/Skyrim:Bleak_Falls_Barrow_(quest)

shes only there if you get the bleak falls barrow quest from farengar prior to clearing out the barrow