Y-frame haulage mechanics

This latest stunt, designed specifically to grab media attention,  tells us nothing about long-distance stone transport that we didn't know already.  It also gave MPP and Barney Harris a chance to flag up, once again, their unshakeable conviction that they have Neolithic Quarries at Rhosyfelin and Carn Goedog, whatever the evidence may show.   Clearly the view is that the juggernaut will not be diverted by some pipsqueak geomorphologists and geologists who fail to see the noble works of man when they look at them -- so the best tactic is completely ignore whatever inconvenient material may have appeared in print.

Anyway, there are a couple of interesting features of the new experiment.  First, the "rollers" are not rollers at all, but 2m lengths of timber cut lengthways in half with the aid of a circular saw.  So they have a flat face which rests on the ground, and a semi-circular upper surface which stays put when a heavy sledge is pulled across it.  Fair enough.  That means the point of contact is very small, and friction is reduced.  But could somebody please explain to me how vast supplies of logs 2m long would have been neatly sliced in half in the Neolithic?  And what sort of effort might have been necessary in order to strip off bark and remove all of the stumps of smaller branches, using just stone tools?

The Y-shaped sledge is also something very peculiar.  How many trees are there in this world that have symmetrical  forks with two equally weighted or developed trunks gently spreading away from an initial single trunk? 

And then there is the interesting method of placing the stone with its long axis not in the direction of travel but perpendicular to it.   This may be OK for a stumpy stone up to 2 m long, but some of the Stonehenge bluestone pillars are longer than that, and to transport those in this fashion would have led to huge unstability, and everything would have deteriorated into chaos on rough or sloping terrain. Even more of a problem on a side slope.   You could overcome this problem to some degree by having TWO Y-frame sledges side by side, with a long pillar strapped across both of them -- but then you would also need split logs twice as long to rest on the bumpy ground beneath.

Now here's a nice idea.  Let's get all those jolly students and their logs and Y-frame away from their leafy London park and down to Pembrokeshire to re-do the whole experiment on the boggy moorland near Brynberian........ and I and some other hostile natives could turn up and throw stones at them, just for fun! (Is that allowed by the health and safety people?)