Interesting theory, and logical.

I always assumed it was more a mental thing.
"I have to make this par putt" versus "It would be nice to make this birdie putt".
It would seem like more of a disaster to miss a par putt than a birdie putt, so you don't go for it as aggressively.
In general people hate losing something more than they like gaining something.

Could be a combo of all of the above

It could be a combo. I suspect, though, that the mental thinking of the value of making/missing a birdie putt and making/missing a par putt changes from a PGA pro, to a scratch golfer, to 6 hdcp, to a 12hdcp, to a 20hdcp and so on.

I would think a non tricky 8 foot birdie putt is approached with normal aggression for a pro, while it might be approached too aggressively or too passively by a 18 handicapper depending on how they are wired...

True.

Interestingly I just played a round where I made every putt I looked at for par and nothing for birdie. Seemed like I was making free-er strokes on the par putts. Guess that's just how my mind works.

Not that it really should make a difference, a stroke is a stroke, they all count the same.

One drill you can do to help with keeping your head down is to put a flat ball marker under the ball and to make sure you are looking at that same point after you hit your putt.

Another good drill for putting is to wrap the putter handle with a towel so it makes the grip a lot fatter. This give you the feel of taking your hands out of the putting stroke.

Actually, they controlled for distance so that was not a factor.

This is very interesting and logical as well. And even though they controlled for distance, I don't think they could control for this factor, specifically the part about a pro choosing where to putt for par from on the green when scrambling.

They usually have more info when putting for par. Like if they ran it 8 feet past the hole, or chipped to X feet and get to watch someone else chip or putt along the same line. Happens way more often for par than birdie.

This is what I was trying to reference. I assumed they controlled for distance.

never thought of this explicitly but it makes complete sense........ has someone (broadie or pelz) studied this? (apples to apples of course)

it's also interesting that i thought that pga pro's really jam putts and don't mind 4 feet comebacks that much. (am thinking of rocco's book about his playoff with tiger at USO) ... but then i saw an article saying if you hit your putt "too hard" the effective size of hole goes down alot.

i.e..... soft putt = more break but it tends to fall into the hole. hard putt = takes out alot of break but doesn't drop as easily.......... and of course you also have pelz' 18 inch donut (i.e. not footprints near the hole)

one nice thing about putting a putt past is you see the break.. and if you play enough break the ball won't be going away from the hole as much as if you play too little break.

No it's not. Every shot counts the same.

The reason I even thought of this is because it is a huge factor on my home course. It is a short and wide-open course and the defence is big undulating greens. They all slope front to back. I would say for random 10 foot birdie putts I can only really be aggressive on a 1/3rd of them. The downhill ones are nasty and anything sideways and slightly above the hole can run out 4 or 5 feet if you miss.

If I miss the green and have a chip or pitch, or even a long putt, I have to be really careful about it running past the hole. So, if I am past the hole, it isn't by much, and I am usually below the hole for par of bogey putts. I don't have the luxury of locating birdie putts always below the hole, because I am not good enough. Though I do try to err on under-clubbing rather than over clubbing.

It doesn't from a mental accounting point of view. We are discussing breakdowns in human behavior here that don't necessarily make practical or mathematical sense.