I'd also have to qualify what I said by saying the surface in question would play a big part. Consistency/irregularity of the surface plays a part - I would say Rory making 55 in a row at East Lake = making 25 in a row at most public courses with the same setup.
Give me a flat, straight 10-footer over a 3-footer with a couple inches of break anyday. What I'm assuming is that the 3' drill mentioned is probably similar to what Phil does, placing multiple balls around the hole, 3' away. If there is any slope at all in that scenario, I'd put my money on making more consecutive flat, straight 10-footers over consecutive 3-footers from "around" a cup.
When I practice putting, I will often use a similar setup, with an eyeline mirror and a chalk line. After settling on a spot that's actually straight (probably the toughest part), it doesn't take long to get in a groove and it starts to become very easy. If you notice, in each four ball set, he doesn't even move his feet between shots, which can't be said for the 3' drill (not to mention the lack of the training aid).