The problem with the argument is the math is lacking. No one here besides Jason really touched on it when he said, 'chart yourself against them'... he's saying if you don't have absolute numbers, show relative ones.
Make up some sort of grid and show all the components (on page ranking criteria, sheer amount of indexable content/products, whatever you want) and then do a link analysis, even by hand, and say, 'to get us in the zone, everything being equal, we need to have more/higher quality links than them too, and here is what they have... so to beat them I need X little ones, or Y med ones, or Z big ones, or some combo in between, and based on simple math, it appears this <insert right answer> is the most cost efficient way to accomplish what you want to do.'
