What is the purpose of eMMC_RSTn?

On the BBB there is a gpio that is connected through a open collector buffer to the emmc reset line. It seems that this is there for the purpose of allowing capes to use the processor pins that are otherwise connected to the eMMC, by holding the eMMC in reset. I’m considering removing feature on a derivative board - just want to confirm that it is not necessary for any other function. If the reset is removed, is it recommended that the eMMC reset be connected to SYS_RESETn, or some other reset source instead?

That is what it is there for. However, it does not work until you enable it in the eMMC itself.