@Seedfork I think part of the problem may be the biological situation and the apparent visible to the gardener situation.
The description below is based on how biologists have classified the way daylilies develop scapes/inflorescences.
Biologically a fan of leaves is produced by the growing tip, the shoot apical meristem (SAM). In daylilies the seedling begins with just one SAM. The basic sequence is for the SAM to produce a number of leaves and then to produce a scape. While producing new leaves the SAM stays the same size or grows larger. When it produces its scape the SAM grows smaller and becomes all used up in producing the stem, branches, leaves, flowers, etc. of that scape. Once the fan has bloomed it is finished. Its SAM is gone. The crown is able to produce one or more new SAMs from the axillary buds that can be found or are developed in the angle between each leaf and the crown. The crown of a daylily is a compressed stem. A new SAM produces a new fan. A new fan can bloom in the same growing season. That is rebloom. The new fan(s) that are produced after the SAM becomes the scape usually appear immediately beside the scape and between a leaf one side and the scape on the other side. Biologically one scape, one SAM, one fan. To produce a new SAM and new fan and a second scape, an axillary meristem is promoted to be a new SAM.
In some cultivars, in some locations and under some growing conditions the new fans do not develop very quickly and one can see that their SAMs had become resting buds for a short time (presumably when a SAM becomes a resting bud the outer leaves of the bud become scale-like). Then one might be able to see that there was a new fan developed from a bud.
In some cultivars, in some locations and under some growing conditions the new fans develop rapidly (they probably overlap considerably in development with the scape) and one cannot see any evidence that their SAMs ever became resting buds. It looks like there is only one fan with a scape lower down and another scape further up. There are no obvious differences in length or width between the leaves below the first scape and the leaves above it and below the second scape.
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There is an alternate explanation for how daylilies flower that some biologists consider explains the situation when it appears that two scapes developed on the same fan. In this case the fan is assumed to have developed its first (lowest) scape from an axillary meristem. That allows the SAM to continue to produce leaves until it finally becomes the second scape.
I suspect that may happen as an accident of development very rarely. That is why basically I consider that all rebloom comes from new fans, biologically.
