The terminology is sometimes too obscure (see issue EMIX-280 for a collection of sub-issues that so state). The following should address your concern.
Rewrite and review the ws-calendar narrative for clarity and precision, including Stop sentence after "inherited" and add discussion of inheritance earlier in document.
Use WS-Calendar Gluon in first reference in each section.
Add conformance section on inheritance to last section.
Terminology needs to be consistent; e.g., a Gluon acts as a handle to a Sequence
Capitalize Interval, Gluon, Sequence throughout as defined terms.