I followed the steps outlined in the Debian-WIki BridgeNetworkConnectionsProxyArp and it works... almost.
I have a Windows PC getting internet from RPI(2B) via eth0 via wlan0(tiny generic 802.11n USB plug) via WiFi router on other side of building!
But... only when the Windows PC has IPv4 address set statically.
I remove dhcp-helper from the Pi and it still works fine, of course, with static IP address.
I set the PC to use DHCP and IP address defaults to the 169.254... number, as you would expect (no dhcp-helper).
I put dhcp-helper ( DHCPHELPER_OPTS="-b wlan0" ) back in the RPI and the PC always fails to get an IP address.
Htop shows it's there, running just fine.
The RPI is getting its' IP address assigned from router OK.
RPI eth0 IP address mirrors that of wlan0.
So, now I'm wondering... Raspbian kernel != Debian kernel => dhcp-helper not work?
Or... (please let it be) is there something silly I need to do that is not mentioned in the Debian Wiki. ?