Switch Control? When and How?

[TicoMan]

Hello,

I have several questions around the Switch Control feature in my Asus router. Hope you guys can help me out.

1. What does the Switch Control feature in my RT-AC88U do?
2. When it is recommended to enable it?
3. Will it improve the speed of the wired connected devices?
4. If I have a switch connected to the router will it do any harm or good?

Thanks!