Chris,
You're just buying their "reasoning" which isn't reasoning at all but rationalization.
There was a time when Ernie Els made a lot of putts. Big putts, cruicial putts, putts that won tournaments. Putts that won majors. All with a conventional putter. Then there was a period where he didn't make any putts worth mentioning. Same guy, same kind of putter. Now there's a period where he's making a few more putts although still not major-championship-winners by any stretch. Same guy, new kind of putter.
Did his conventional putter suddenly start wiggling around in his hands a few years back? Or did he maybe, you know, start not putting as well because of his own self? If he gained confidence from jabbing the putter up against his body, he might just as well have gained confidence by giving his life to Jesus or because Bob Rotella whispered a magic word in his ear. IT WASN'T THE PUTTER AND IT WASN'T THE ACT OF TOUCHING HIS BODY WITH THE PUTTER.
It could well happen that a few years hence he starts putting badly with the long putter. A lot of guys when they happens have switched back to a shorter one, not anchored and found that their putting improved. Did those guys' long putters suddenly pointing itself in the wrong direction? Or is it that they just started putting bad and needed a change?
You can't prove that a different way of putting is better by pointing out a guy who wrote a magazine article saying it helped his game. You've got to look at totality of anchored-putting players vs. conventional-putting players and ask whether either one has a demonstrable advantage in putts made, all else being equal. I've seen no such argument made.
P.S. I think I'll adopt that name for it, the Act Of Touching Ones Body With The Putter. Sounds sort of like a quasi-religious (or at least quasi-sexual) ritual. Which I guess it basically is, in some cases.