In short: asic producers can release a new asic version for every N as previous generation asic miners will be too power hungry anyway.
I agree. Scrypt-n is however much more expensive to implement is an asic! And changing to scrypt-n would remove the threat of the currently announced asic miners. And what is even more important: it would scare asic developers from trying again for scrypt-n. You only need to show your determination not to allow asics for your coin!
I fear that Scrypt's way to implement RAM, and now Scrypt-N's to implement way more RAM, will have a boomerang effect in trying to prevent centralization, creating more centralization as an unintended mid-term consequence.
The Litecoin devs are right in one thing: If a coin is mine-able in a GPU, it's game over. ASICs are just a matter of time from that point onwards. The thought however of making the ASICs expensive through much RAM, is something that will escalate ASIC prices and reduce the affordability of ASIC miners for the masses.
If RAM was not a part of the equation, a greater degree of decentralization could occur once a coin moves from the GPU to the ASIC cycle of mining, through affordable ASICs that normal people can actually buy without paying a fortune. So the fact that ASICs will have to be very costly in order to have much RAM, is not really good down the road.
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