When you carefully study the inscription of the Phaistos disc, at a certain point you'll realise that it consists of "elements", by which I mean: two consecutive signs in a signgroup, which feel familiar, because they are repeated in other signgroups. If you then take the full consequence of this discovery out of confidence with the inscription, you'll find that it has an absolute amount of 70 such structures. These 70 stem-elements I've placed in the upper half of the above quadratic arrangement. Now the inscription unfortunately/fortunately shows to be mischievous, (this is probably the reason why its symmetries have never been acknowledged before) because the sign-materiale within the stem-elements also exists outside the stems, as isolated and single symbols.
Now my great idea is that the isolated signs are abbreviated from two signs `from stem-elements´ I've placed those "reduced stems" in the lower part of the arrangement. All visible signs in the reduced (shortform) stems are hold in black, as were the stems, and the abbreviated signs are painted light greyish.
Now the credibility of these 70 elements lies on the structures that they reveal, for instance the perfect symmetrical interrelations between the stems and the reduced stems, as seen in the Gnomonical arrangement, which undoubtly can not be explained from language or linear metrics (Under the device : Nothing new beneath the sun, a reader would soon have brought to light a similar splendid linguistic analogy, had it been language). On the other hand, calculations and counter-checks are fundamental principles in building up ledgers. Or if the calendar is the primary factor of the inscription, then perhaps the hieroglyphs could be describing the movements of the sun versus the moon through the year, or a similar system of congruency
NB Each of the six colored groups in the above, by functions determined arrangement consists of total 22 stems and 11 different forms
You're looking at a minutely duplicate-system. Nothing less than a revelation concerning this topic ! Together with the detached 29 remainder-signs and their abbreviated parts (see below) the disc consist of 348 units and 17 strokes.
This means, the long awaited break-through to this old enigma: not a grammatical system, but a perfect quantitative system together with "a 365 day calendar". Judge for yourself.