These costs, as it has been explained to you repeatedly, are trivial given incremental centralization. In other words miners are incentivized to centralize so as to limit their orphan risks and create larger blocks.
No, Gmax has been hand-waving about some hypothetical future network configuration (that is unlike what bitcoin is or has ever been) that many people with broader knowledge of economics disagree with (assuming it's even physically possible).
Right now--based on the average network propagation impedance--it would cost about 4 BTC to produce an 8 MB block, and VASTLY more to produce a 1 GB block (if the limit were removed). Connectivity would have to improve already just to make 20 MB blocks economical...
You're lieing and a quick check into your email correspondence with him can confirm.
He is describe absolutely real and existing mining configurations which promise to worsen in the future given a removal of the blocksize cap.