Greg Norman knows a little something about scar tissue, so what he has to say about bad experiences in golf is practically gospel.*
Norman, who will be lead analyst for Fox Sports' coverage of the U.S. Open, believes each successive time Tiger Woods posts a high, humbling number in competition that it becomes harder for the 14-time major winner to regain even the form that led him to eight PGA Tour wins in 2012 and '13.
"It's a massive effort, mentally and physically, for him to get himself out of this hole he's in," Norman said in a pre-tournament conference call. "The more he shoots 85, or extraordinary high numbers, the harder it is for him to get out of that hole."
Woods is working with his fourth instructor, Chris Como, as a pro. Each successive time, it's become more difficult for Woods to figure out the changes, needing more time to get equal or worse results. Moving from Butch Harmon to Hank Haney costs Woods about 18 months, but the results were about the same. Going from Haney to Sean Foley took a little longer, though Woods' progress was hampered by injuries. The results so far with Chris Como haven't been good, and Norman believes Woods simply can't put in the time to get it right -- if he ever does.
"Your body doesn't recover quickly, or as well, like it used to when you were in your 20s and 30s," Norman said. "He's got that mountain to climb."

Ryan Ballengee is a Yahoo Sports contributor. Find him on Facebook and Twitter.
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