Unreasonable setting of Approach in HVAC:Template:Plant:Tower

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When we use HVAC:Template:Plant:Tower or HVAC:Template:Plant:Tower:ObjectReference, the expidf file automatically sets condenser water temperature reset control by SetpointManager:FollowOutdoorAirTemperature as follows:

SetpointManager:FollowOutdoorAirTemperature,
  CHWloop CndW Temp Manager,                               !- Name
  Temperature,                                             !- Control Variable
  OutdoorAirWetBulb,                                       !- Reference Temperature Type
  0,                                                       !- Offset Temperature Difference
  80,                                                      !- Maximum Setpoint Temperature {C}
  5,                                                       !- Minimum Setpoint Temperature {C}
  CHWloop CndW Supply Setpoint Nodes;                      !- Setpoint Node or NodeList Name

I think Offset Temperature Difference can be regarded as "Approach" of cooling tower. It's set to 0°C, which is unachievable in principle. A quite large range of Minimum Setpoint Temperature and Maximum Setpoint Temperature is also unnatural.

As mentioned in this post, cooling tower is controlled to deliver an unachievable approach of 0°C, and therefore we get high fan energy consumption. When I use HVACTemplate, I always edit expidf file to change this SetpointManager:FollowOutdoorAirTemperature setting.

Is there any reasonable reason why Offset Temperature Difference is set to 0°C by default? I may have overlooked something.