I just tried this in VIRL with two routers sharing the same ID (2.2.2.2). The router was able to accept the routes from a router which has the same ID as itself and the hosts in the routes were pingable.
This seems to be in violation of what you s...
Can someone please clarify if EIGRP IDs have to be unique from routers on the same LAN? I know they should be, but will neighborships form if two IDs are the same on the LAN?