@The:
I wouldn't even call it remotely a plot thread. Doc and Jackson have addressed this many times ("Why do people care about Triana's dopey friend Kim?") and have stated that they never meant for that line to be taken the way people have taken it.
She was mistaken for a villainess by both the boys and Dr. Girlfriend, and said something along the lines of "She thought I was a bad guy, I am so gonna to do this" and, later, "I'm gonna be a supervillain."
At the end of the episode when Hank and Dean do their Team Venture signal, Kim says to Triana, "I think I just found my first archenemies."
Maybe the creators only meant it as a one-off of playful banter, but in a series LOADED with crazy people who take up professional supervillainy to arch someone that pissed them off in college, or over incredibly minor offenses, in a show where characters with only a couple lines of dialogue come back to be villains all the time (like Monarch Henchman 1) it sure SOUNDED like they were setting something up, especially when she has an entire conversation with an established villain, is handed a guild card, and then has three different lines saying she's going to do it. And she had a ton of screen time in the ep.
That's not really a single misinterpreted line, thats an entire misinterpreted 3 or 4 minute scene, if thats not what the creators really intended.
The two seasons of not getting back to it was pretty much the only clue on the show towards the fact they didn't really mean it. Stuff said at conventions and interviews doesn't count.