Do Proposed BuildingSegments need to match Baseline BuildingSegments?

[JacksonJ-KC]

To put this question into context, I am trying to understand how to write the RMD of a Proposed HVAC System (DOAS for example) that serves an entire building which includes multiple "building segments".

Would the proposed RMD have the same building segments as the baseline RMD, and one of the building segments is selected arbitrarily to contain the HVAC system, then every DOAS terminal is able to reference the DOAS HVAC system, even if it is outside of its building segment?

[JacksonJ-KC]

To me this seems like an issue that stems from HVAC Systems being inappropriately located under BuildingSegment instead of Building and perhaps that was a solution to an issue within a specific ruleset

[weilixu]

Baseline usually follows the convention in the proposed. However, some tools have no building segments so I am not sure a compliance model shall be the same as the proposed in terms of zone grouping.
One example I can think of is DesignBuilder. DB introduced the concept of blocks between building and zone level since the beginning. The way their guided Appx G generation is keeping those blocks the same between proposed and baseline.
Can we think of other examples?

My impression of proposed design model is that zones are grouped by a single secondary loop or an AHU. If a building segment follows this design principle, then it is technically one HVAC system per building segment.