Well, I think most of that comes from ignorance as to how the devs go about testing the game. This particular scene aside, you have to consider how many iterations there are during any given cinematic, which can only be even partly understood if you sit and look at all of the options in succession, as I've done on several occasions. There are the various options the player gets, then the NPC responses to each of those. Some of those NPC responses change based on who your PC is (race, class, origin), your relationship with them, or even based on previous events in the game; some responses, and further player options, alter based on your choice earlier in the conversation. So there are a lot of variables.
And while I would like to think that the devs, particularly those that are involved with writing individual characters, would sit down and go through everything related to their character to make sure it's all working correctly, I can see how something like that may be lost amongst all of the other myriad things. Solas was written by Patrick Weekes, who also wrote The Iron Bull (another romance option), and Cole, in addition to any of the other miscellaneous characters -- perhaps those that carried over from the The Masked Empire -- and various assigned story quests and plots. And then of course after they test a lot of their own content, they just become extra bodies to test various other parts of the game that don't have to do with writing at all.
So I can understand all that. But as I said, it would have been nice to see a fix for something plot related via a patch once it was known. Ah well.
At any rate, sorry for the digression.