It has been addressed in some threads, but I believe this isn't really up for debate, is it? Hasn't it been proven scientifically to be better? I can't remember the facts behind the tests, but pretty much everyone that I can recall seems to be coming back that it is in fact better, or at least in most situations. It seems even some pros hesitant to do it at first, are now leaving it in for long putts at least.
Now, whether you can stand looking at it and personally believe it while putting, is a different story. I'll admit that when playing alone in previous years I've done it just to save time if I have a long putt, it's just now legal
While playing, I will most likely just do whatever the majority of the group wants, again, to save time. I don't mind either way honestly.
Yes, it is an advantage and there are studies that show this. After the current year on tour, we'll have even more evidence that flag in leads to better scoring.
No, it is not improving the pace of play. In fact, right now if anything it is slowing things down as players have to ask or request for the flag to be removed or replaced multiple times on every green.
The USGA has admitted they didn't even look at the data on whether the flag in represented a scoring advantage. They just thought it would improve the pace of play. This is moronic. On the tour where ONE STROKE can mean $100,000.00 or more, they didn't think professionals would take a look at the data as to whether the flag in or out gave them the best chance to hole a putt? Are you kidding me???
IMO, flag in represents several advantages.
1. The dampening effect of most flagsticks allows putts to drop that otherwise would have lipped out, or ended up farther from the hole.
2. With the flag in the hole is more easily broken into segments, which sometimes helps in aiming.
3. Flag in also gives you a reference point at eye level, which can help eliminate some of the perception issues associated with looking from five and a half feet up looking down at ground level.
4. In some cases where the ball comes in too hot, the ball will end up closer to the hole by crashing into the pin as opposed to running over the hole. Thus eliminating a 3-putt now and then.
Yesterday I was out practicing a bit and playing 3 balls. I putted one and it went and wedged between the flag and the inside of the cup where the top of the ball was level with the surface of the green. My next ball was 10 feet right over the top of that ball. So I am putting at the hole and the front 1/4 of the cup effectively has a lid on it. My ball rolls right over the top of the other ball and hits the pin square, then rolls right down my wedges ball to the left inside the cup. That pin really is a huge backstop for the ball.
The only caution I would have is to make sure it is all the way pushed into the cup and not leaning towards you before the putt. Also be aware of the wind whipping it back and forth.
I believe it is an advantage to leaving the flag stick in most of the time.
Wind, how the hole is cut, and what kind of flag stick is being used will have to be play tested still. I'm not on a tour so courses are set up differently. I've heard through television way down the grape vine that studies from Dave Pelz and MyGolfSpy show it is an advantage.
There have been studies done that show the ball is more likely to go in the hole with the flagstick in. Ive actually been leaving the flagstick in for quite a few years now when playing causal rounds alone.
We have discussed this before and there are varying opinions on the issue. Until recently, I was firmly in the "leave it in all the time" camp. After my last few rounds, I'm moving to the "I'm going to pull it for 'short' putts" camp. I haven't ironed out just yet what qualifies as 'short', but I know I've been missing way too many putts inside 6' or so. Yeah, I know it's 100% mental. Yeah, I know that statistics show it's more likely to go in with the pin in. I also know that those statistics mean jack-**** if I push or pull my ball completely outside the hole. It's all in my head, but I'm going with it for now. The pin will come out when I'm relatively "close" to the hole.