@JPB,
My percentage of getting those right is 15-20% ...just a guess. I've done this...on average...a couple of times per season..maybe 4-5 times. I tried to talk myself out of making the change too.
Each time, the team to which I've switched looks like they're going to win until the very end of the game...just to make matters worse. Steelers really wanted to make me nuts last night!
Each time the dialogue goes the same:
"I just got this feeling."
"The devil made me do it!"
"The home team HAS to win even though these teams are pretty close."
"The experts say this team has to win!"
"This team always beats them in their stadium (or some such rationale)."
Last but not least, if it's close and the home team gets to the game's end...the home team's kicker can always make a difference.
ARGGH!