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CAN-Bus, one 60-Ohm instead of two 120-Ohm resistors

Sorry for my limited English ability and Technical ability.

It is very common in our company that, the engineers don't care about (or don't know) the termination resistors on a CAN-Bus. They just simply put one 60-Ohm resistor between two or several CAN-Devices (mainly for testing purpose). I know this is not standard, and I don't like this workaround. I tried to figure out why such a workaround is bad, but failed.

It seems that many engineers use such a workaround.
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www.microchip.com/.../m177894-print.aspx
a single 60 ohm termination for lab testing when bus is only a few feet (probably not allowed, but it works).

www.microchip.com/.../m144034-print.aspx
If you don't have two 120-ohm resistors, you can accomplish the termination (on a small network) with a single 60 ohm resistor(120 in parallel with 120 is 60) or anything close 55-65 is fine.
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I found a document saying this workaround is a mistake, but it does not provide why.
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www.scribd.com/.../SAE-J1939
The bus is linear and should be terminated with 120-Ohm resistors at either end. It is a common mistake to use one 60-Ohm resistor instead of two 120-Ohm resistors. This does not work correctly, however.
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What is the disadvantage/mistake, if we use one 60-Ohm resistor instead of two 120-Ohm termination resistors on a CAN-Bus, assuming the communication distance is not very long and only 3-5 CAN-Nodes (Devices) involved? In another words, when will such a workaround fail to work?

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It is very difficult to find another job in southern Taiwan. So I am still struggle with idiotic things, and busy in urgent projects.

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