Daniel;
This is an especially strange comment, as almost everyone who peers, interconnects in multiple places - thus, exceeding the capacity of a single interface.
I mean peering speed between a single pair of ISPs at a single exchange (or peering) point exceeds that of a single interface. And, if you need many, say 10, interfaces, l1 have all the flexibilities Vadim want.
Layer 1 peering (or pooling, as it's more usually known) is great for interconnecting fiber networks, fast provisioning, and all that.
You may say that we are not ready for full fiber networking, yet. But, we, at least Randy, are talking about "the right path". OK?
However, I fail to see the connection between Layer 1 interconnection and an IP exchange point of any kind. This seems apples and oranges.
Except that there are private peering at exchange points.
Layer 2 exchange points are the only efficient way to go for IP traffic. History and the "invisible hand" of the market have endorsed this path.
It is merely that an l3 exchange point over an l2 shared medium is a bad idea. Masataka Ohta