Apple IIe/IIc/IIgs setups

[admin]

That is correct. It is not optional. Without cutting the traces and making the jumpers, DTR/DSR will not work. These are required for flow control on the Apple IIc/Laser 128/Apple IIgs (internal modem port). So, if you don't cut the traces and add the jumpers then you don't have flow control. You also don't have the ability for ProTERM to know when the modem has lost carrier.