Hey Ccooper, Tourny greens are a pain in the anterior at first but after you play them for a while, you will like them. Big clue though, approach shots are crucial when playing any greens but moreso in tourney greens like Oakmont or Congressional. Get as close as you can (sort of goes without saying) but making a 25 to 30 foot putt on these greens is a royal PITA.
Practice tourny greens in your clubs tourneys. Get the owner of the club to put some tourneys out there with unlimited play and spend a lot of time on them. Different courses every week too, they all don't play the same nor the same speed. Some are much faster than others and when you have played them for a while you will see that the slower ones are about like VFG's.
A good rule of thumb for most tourney greens on putts longer than like 10 feet is 75% rule. 30 footer putt it like it is 22 and 1/2 compensate for break and uphill/downhill lie. 30 foot putt with a 6 inch uphill grade, calculate it as a 36 footer and putt it at around 27 etc. and it varies from green to green but not by a lot. After you have used that fort a while, you will see where you need to make adjustments based on your skills and experience.