While I do agree with the argument of how a virtual ball could possibly cost almost as much as a real one...I feel that it is not quite on topic with what the OP had in mind for this thread and we should try stay true with his intentions.
Golf is a game that is bursting at the seems with money glittered over the top players on both the major Tours. Sponsors are more than willing to fork out copious amounts of money on star players to enhance their own image and the image of their gear being used. Often this marriage is a match made in heaven, however every now and again this fruitful connections form s a tear and eventually they split altogether. Often the new sponsor a player turns to can be just as if not more profitable than the last for the player, however there are instances where it is not.
Case in point, the late Payne Steward. He joined a Spalding after having a fantastic relationship with Wilson for many years. The year before he made this transition he was 6th on the money list and looking to close in ever closer that that crowning spot. The same time the following year after being forced to use Spalding gear he dropped down to 123rd on the money list.
Nick Price did something similar if not a little more reckless. He joined a budding company called Atrigon with the promise he could design his own set of irons but on the premise he must play with their driver, the only club the company had in production. His form in the following two years is more than a suffice record of how this marriage did not bare much fruit.
Cory Pavin found himself in the same boat after winning the 1995 US Open and followed it up with a solid year in '96 while using Cleveland gear. His decision to join a Japanese manufacturer would see him being out of the winners circle for the next 12 years!
Rory is a talent that comes along just once in a generation, however the talents mentioned above could almost be regarded in the same esteem.
Golf is a game of feel. Once you have that touch it is hard to stop a top player from claiming all the cookies over the weekend, and just the grey matter between your ears could stop an inform player from following the golden brick road to the winners circle. However if you cannot find your touch because the gear you're using feels somewhat alien, you have to deal with trying to find that touch and dealing with the thoughts in your head at the same time.
It could be that he is in that transition phase and soon he'll find his feet and jump back on the horse...However, history shows that once great players have found it hard to get onto a horse they do not know or trust...The horse may be fast, but if you cannot ride it, it's as good as a donkey on a dust road pulling a cart of beans.