How many Tibetan monks practiced meditation in "old Tibet"?

One aspect of the notion of "Buddhist Modernism" is that in modern history (ancient times aside) even the Theravada monkhood, let alone the laity, did not generally meditate, until the Burmese/Thai revival due to Mahasi Sayadaw and a few others in the 19th and early 20th century. (http://meaningness.wordpress.com/2011/07/07/theravada-reinvents-meditation/) Yet, there is still the question of Tibetan monks, given the vigor of that tradition back to its introduction into Tibet. McMahan suggests (without any references!) that very few of them meditated: > Tibetan forms of meditation have gone rather abruptly from being the > province of a small number of specialist monks in Himalayan hermitages > to being offered widely to the public in countries all over the globe. > (McMahan, David L. (2008-10-17). The Making of Buddhist Modernism (p. > 187). Oxford University Press. Kindle Edition.) But my impression is that in "old Tibet", that is pre-1950's, a fairly large fraction of the (very numerous) monkhood did practice meditation, via tantric sadhana and/or mahamudra. Does anybody have actual references bearing on this? I realize there will be no quantified data, but how about biographies, reminiscences and other historical literature?