This sounds to me like bullshit criticism. If you have a circular flow, the only way to know the total volume in the system is to measure value added. The value added approach does not pose any problem for the economy as a whole - it starts posing such problems only when you start breaking it up by activity or institutional sector. The value addedd approach shifts intermediate consumption to the final consumer on the assumption that intermediate consupmtion cost is included in the market price of the final product. The commodity production and distribution process thus appears as a "value conveyor belt" rather than creation of value - which has a Marxian aftertaste to which those trolls most likely object. This is why the value addedd approach pictures US computer hardware industry as a minuscule contributor to the GDP which by definition includes only production within national borders (a point I raised re. Doug's post).
I think that the bone of contention is the question formulated by Marx: who creates or adds value? Unlike Marx, the national accounts count value added by capital (but perhaps not as much as bourgeois trolls would like to see) but exclude value added by non-market activities, such as gray economy or voluntary work. I am not sure, however, how national accountants break up the GDP by fields of activity or institutional sector.
The bottom line is that the objections you cite appear to be more political than technical.
regards,
Wojtek
PS.Sorry for posting over limits.