IMHO Litecoin is doing just fine without this and it will continue to do just fine without this. Bitcoin needs this more than Litecoin needs this. If you can't see the usefulness in Litecoin at this point in its development, then just get to steppin'... we don't need you.
a) it would be exceedingly hard to properly develop detection algorithms for "malicious reorg" detector
Reorg shows up in the debug output immediately in the client
It's absurdly easy to detect (just look for a chain that's been reliably mined for 6 blocks/1 h and then at 1 h the 7 block fork is detected --> report this to user via pop up)
The likelihood of two totally different chains size max of 6 MB (6 blocks) existing on the network at the same time and both being reported to a vast number of different nodes with neither group of nodes interacting is really, really unlikely
I am aware of those facts.
However, I believe you missed the part where I explicitly stated the qualifier "malicious".
Detecting a reorg is trivial. Determining whether it is an okay reorg or a "bad" reorg does not seem so.
Part C is where the process would break down and where litecoin would shine. In March, the "heavy hitters" in IRC had the benefit of being able to reliably contact and influence the majority of the hash power in a short amount of time and persuade them to implement the desired solution, and they had the benefit of a ready-made solution (a version to roll back to) so that nobody needed to do anything objectionable. Without both of those, the devs in IRC would have had far less power than they appeared to enjoy.
If a core feature of Litecoin were that mining nodes can accept operator(user) influence, those mining Litecoins get a decentralized pulpit from which to announce their collective opinion as to which fork of the Bitcoin chain is correct. Even in the absence of that, Litecoin can implement automated validation rules with respect to the Bitcoin chain that would be too cumbersome for Bitcoin to adopt... example, Litecoin can be programmed to automatically refuse to endorse large Bitcoin reorgs without gaining explicit operator consent, which for a well-connected Litecoin node is typically a good policy.
I don't see why Litecoin is required here.
I mean, I realize that in this scenario, it is, essentially, a large backup tape.
But what exactly prevents BTC from, just, you know, keeping the reorged-away blocks for a little while longer and pleading the node operator to investigate "suspect" reorg when it occurs ?
Both solutions provide, essentially, the same functionality - block material is kept around for a while longer, so that human-op can decide which side of a fork he likes the best. But one requires mutual inter-operation between two cryptocurrency nets, while the other does not.
I, so far, fail to see the advantages to the "inter-operation" scenario beyond
"let's give litecoin a sense of purpose" and
"it would be a shame if GPU miners starve".