I'm honestly a little surprised at this...the majority of players I've talked to have always chosen to kill Bartrand/give Varric idol. Guess I'm not such a special snowflake afterall...*weeps bitterly* 
Gaming at the Sadists Convention - Adventures with Mrs. Chestbeard.
Was it really that many rivalry points?! I said no to her too, but all I really remember is her yelling at me and saying she hated me. 
I was honestly just weak against Varric and didn't want him to dislike me. *sigh*
Will do... I feel like I should have at least one playthrough where I don't change anything so I can see the true consequences of my actions, so it will probably happen... even though it's scary. And The Keep makes it so tempting to easily fix that. xD
As I understand it, if you're on the Friendship path with Merrill and you don't help her fix the mirror, you go from Friendship X to Rivalry X-15. So if you have Friendship 80, suddenly you drop to Rivalry 65. Which is a ton of points, when you get right down to it.
I have a Hawke who gave Varric the shard, but he's pretty low on my list of characters to continue. One of us will see it eventually, I'm sure.