Barney's proposal was not as awful as people make it out to be.
God, I am gonna get slaugtered for this.
First of all, Patrice wasnt manipulated or something. She just was a really good person that tried to help barney, because she wanted the best for Robin, despite her attitude. She didnt have to undergo Robin's behavior BECAUSE of the plan, robin was already awful to her before she found out that she and Barney were supposedly in a relationship.
Barney had to tell robin all of those lies in order to get her back. Yes it was manupulative, but Robin loved barney and she probably wouldnt be happy for the rest of her life if she didnt express those feelings. She couldnt do that (banrey had tested it many times but she said no), so he "helped her" by doing it himself in the most complicated way so she would accept the proposal.
The only bad thing I could think about it is that barney chose to do it on ted's big night, but its understandable because he wanted ted to bring robin as a plus 1 to test her feelings, and that was a way of him approving them.
In my opinon it is the most romantic moment of the series.
*EDIT*: I did get downvoted to hell for this, but at the end of the day, 30+ people agree with me and thats good enough for me.