I'm not sure about this but it's better than only disable it like in older version.
I guess it disable hacking tool detection system and stuffs and simulate to reply GG packets.
Can the server tell the differences or not? I don't know.
Edit:
For anyone who play on private servers, for example: l2j.
Let me tell you that L2Walker itself is designed for official servers.
You can try L2.NET instead.
Edit:
Recent IG L2Walker can disable GG for you.
If you want to disable GG without L2Walker, try this:
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