See here (See overleaf: Mufasa variation on attacks) the full description of the variation on attacks.
Tl;dr - LM penalize transactions for arriving later than they should, offering protection against a class of attacks in which subtangles are created in secret and then published all at once. In this variation, the protection of the LM can be avoided by using the fact that unsolid attacks are ignored by the random walk.
LM is a broader idea: it’s “I, as a node, make decisions based on my local picture”. This “local picture” includes the arrival times, but is not limited to them. Specifically, in https://email@example.com mentioned the idea of @alon-e that one can use the solidification times instead of arrival times; this I think would take care of this attack.