The shape, look and feel tick all the necessary boxes for Woods, but there's a piece of the equation that doesn't check out.

"That's a lot higher," Woods points out after taking a smooth cut with the iron. "[The iron] looks sweet, but the window is different."

Despite hitting shots that routinely go 192-195 yards with roughly 6,700 rpms of spin, Woods knows a tweak is needed to lower the launch angle. Keith Sbarbaro, TaylorMade's VP of Tour Operation, suggests checking the center of gravity location against one of Woods' old sets to ensure they match up.

"This is why we test," Woods says with a grin.

Finding a new set of irons for one of the greatest ball-strikers in the history of the sport is akin to putting together a puzzle with 10,000 pieces. Eventually, it will all come together, but it takes significant time and effort to get there.

Woods recalls knowing it was time to find a new iron set when he wore through the plating on three clubs in particular - the 8-, 9- and 7-iron (in that order). It was at that point he started the unenviable task of cherry-picking clubs from eight or nine sets to get the CGs to match. With the rise in iron technology and design, Woods knows he doesn't have to go to those lengths to find a new set.

Asked what separates Woods from other high-level professionals when it comes to his testing habits, Sbarbaro points to his unwillingness to adapt to the equipment he's testing.

"He doesn't adjust," Sbarbaro said. "He swings the club. The only other guy I've worked with a bunch, as a friend, who does that is Phil [Mickelson]. They don't adjust. So many guys will hit an iron high like Tiger did on the first ball and then they'll hit it lower the next time. He's a tough critic. Tiger doesn't adjust to the equipment; he makes it adjust to him."

Welcome to testing with Tiger Woods, an old-school gearhead who provides brutally honest feedback when he's working through new product - even when the cameras are rolling, as they were on this particular day as Woods worked through a myriad of TaylorMade gear during the 90-minute session.

When it comes to pinpointing the differences between his current sticks and a potential contender, Woods is wired to recognize even the most subtle change when he picks up a new club, beginning with the way it feels during the initial waggle. A number of times during the session, Woods verbalized to Sbarbaro and Brian Bazzel, TaylorMade's VP of Product Creation, if a club passed the waggle test before ever taking a swing.

"This club feels great going through the ground, especially when I waggle," Woods said early on as he was getting acquainted to the prototype 6-iron.

Woods told PGATOUR.COM during a one-on-one interview at Medalist that the waggle has been a part of his game going back to when he initially began playing golf, and was instilled by his father, Earl Woods, who believed in trusting the hands and letting them guide the golf swing.

"For as long as I can remember, I've always waggled the club and tried to get a feel for it," Woods says.

The prototype 6-iron passes the waggle test but still doesn't match up to the launch window Woods is accustomed to seeing with the re-badged set of Nike VR Pro irons currently in the bag. The good news for TaylorMade? It's close.