I picked purely on gut except for when I went into week 17 and I was about 4 or 5 points back and picked some underdogs purely because I needed my picks to be different to the leader in order to try to catch him.
Under your system, that would have been rewarded even more with the extra half point.
Whether it would have affected how I picked across the whole season? I don't know. I must've picked underdogs on gut instinct a number of times but I have to assume that would've increased with the greater potential reward. This sounds like a study in psychology as much as anything else.