Even if they fix this, which would only require them to change the trigger for receiving the letter from Triss, it would only slightly contribute to consistency of the romance. In my opinion one more dialog scene with Triss, either on the boat or before the final battle would be required to make the whole Triss experience feel much better. This change would also not require them to alter the main story in any way, simply give us one more chance to talk to Triss, rather then her saying the already infamous "Well?"
There is more to this too I think...we have all read about or seen the stills of the proposed scene from what looks to be Triss' flat in Novigrad. If that scene is indeed a full bore, 'we are in love, forever yours' type thing, maybe something left over from early beta or an in house test, its possible they might slip that in on us. It would be a perfect addition to the return to Novigrad section. Triss would leave a note for Geralt to meet her at her old flat, she needs help with something...

...add candles and the love music background...AND some good, solid dialog that would be time sensitive, referencing Yen and 'how is Ciri going to take this' kind of things.
In my opinion only, that would go a LONG way to helping this romance feel fulfilled. It would need another endearing moment near the end and something special for the new ending they should add to complete the series but...at least this one scene would make us feel better about the relationship choice.
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Also, one more thing. I have seen people(on other topics mostly, but even here) saying that adding more Triss content would somehow disrupt the main story or detract from the experience as a whole for the ones that didn't care for her or romanced Yen, but I don't see how adding one, lets say 2-3 minute scene with Triss in the latter part of the game would affect them or the main story at all. They wouldn't even notice this since they probably wouldn't bother talking to her at all. But it would mean a lot to people who did like Triss and felt that she was nothing more than a random NPC in the later portion of the game.
I think that most people who do like Triss are people who played and enjoyed previous games.Unfortunately I feel that the priority for TW3 was:
People who read the books>>people new to the series>>people who enjoyed previous games, but haven't read the books.
Again, agreed! Hell, the 'node' to spawn the intimate Triss scene wouldn't even be available if you didn't choose Triss AND dump Yen...those who want Yen wouldn't even see an option, they'd never get the note Triss leaves for Geralt, for instance.
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Agreed. This is why I was stating narrative pacing and sequencing was part of the issue of why Triss felt displaced as a romance option because they featured her so early before the Yen interaction was even undertaken. The reason she is lacking in KM and the final act may be due to time and resource constraints but it's glaring for those who romanced her or not. She is simply not the Triss we saw in the first half of the Wild Hunt or in the previous games.
Well said! I know folks may be getting sick of this conversation always coming back to the perceived lack of effort on CDPR's part where Triss is involved...but I just see too much fog for there not to be foglet in the house with this one!