No its not good.
Tell him to use one router with Wan pluged into the modem, and pluged into computers.
Then use only the LAN ports of the second router as conputer ports. Leave the WAN ports empty.
The two routers should share the same ip network (both 192.168.1.x)
Make router1 192.168.1.1
Make router2 192.168.1.2
Problem solved .. and the correct way to do it. In this way one is a router, the other is just a switch.