Confusion in reference to segment start point on the sample timeline

[komar007]

In 18.3, just before Example 8, there is a statement:

If using $Time$ addressing, the value for each segment reference is the segment start point on the sample timeline, in timescale units ([DASH] 5.3.9.5.3).

The definition of segment start point is provided via a link and references the MPD timeline, which can be understood as the earliest presentation time of the segment, converted to MPD timeline (via availabilityStartTime, Period@start, PTO, etc), but the part on the sample timeline suggests conversion back to sample timeline, which seems a bit confusing.

Wouldn't it be more clear to simply refer to earliest presentation time or introduce definitions for two versions of segment start point, one based on sample timeline, and one based on MPD timeline?