No, they initially wanted "rigorous and extensive" testing involving sending sample boards to them to "ensure" compatibility with SLI, which drives up the cost of the boards. Boards with NF200 chips were automatically given SLI, but those that weren't, had to be individually sent in. Then nVidia would give them a special code to put into the bios that would allow the drivers to allow SLI. That was before the 5 USD per board thing.
because there wasn't enough bandwidth for tri and quad setups. That came to a end with Intel bringing out QPI interconnect on their chipsets where nvidia had no option but to issue it without the nf200. Intel found a way to increase the bandwidth without the need of the chip. Intel proved it they have control over it with the x58 P55 mobos. Restricting the P55 where lucid hydra or the nf200 is need for quad or tri setups but clearly showed with the qpi which is basically the dmi connection with increased lanes. Boards weren't put thru rigorous testing. Anyone could see with the scaling quad and tri setups was out of the question without a duplexer. The memory controllers was still on the chipsets aswell. Pci-e devices make most of their read and writes directly to the system ram.