By Jaime Diaz   Jack Nicklaus is 76. A big number, but thirty years after winning his final and most glorious major championship, it’s actually a sweet spot.  Though he left the big stage a decade ago with a final birdie at St. Andrews, the Golden Bear’s legacy keeps expanding. With Tiger Woods’ assault on 18 majors stalled and aura of inevitability over, Mt. Nicklaus has become both more majestic to behold and that much steeper to future climbers. Brandel Chamblee recently made a