Very interesting and excellent article, I liked the fact that Green doesn't hide the details. He says it like it is, I didn't know that to get another 10% on the wind tunnel model, the cost runs up exponentially and admire them for doing what they have done with their limited resources.
At the end of the day, it all makes sense. The more money the team has, the more they can burn off to gain a fraction of a second here and there and that's why the budget cap will be a super effective tool IMO. It'll make these fat cats think twice on how to make frugal developments and not splurge on some radical concept because they could afford it and no one else could or we as spectators pay the price for having dominant teams like we've seen in the past.
Incidentally I read somewhere where people were critiquing Ferrari of the Schumacher era where they had endless budget and testing and so they were dominant. My question to them would be, did limiting only the testing part give teams like Mercedes, Ferrari and RBR a different result?