No idea if that is wrong method, it's just not one that, apparently, has a good success ratio.
My first 'extraction' experience, if you will, was with Madrona leaves for the relief of poison ivy and oak. Took 14 hours at slow roll. I always felt that it required the attention.
My preparing for aya ceremony, teaches me patience and reverence. Not saying that the efficient sounding method won't work, I've no idea but there is more to be gained than just the mechanical result.
Virt
TIME; Natures way of making sure everything, doesn't happen at once! author unkwn