Golfer Mark Calcavecchia earlier today birdied nine straight holes (the third through eleventh) to set a new PGA record. Such a record reflects not only great putting, but also great shooting at all stages to put oneself in position to have makeable birdie opportunities. Quoting from the above-linked New York Times article, "[Calcavecchia's] nine birdie putts were from 12 feet or closer." Even if all putts were from standard length, however, they'd still be more difficult than, say, free-throw shooting in basketball. Whereas a hoop is a hoop, golf greens have subtle curvatures, which require players and their caddies to develop an ability to "read the break."