Ready.
Even without any Ph.D. work, anybody could replace the predicates in E-net procedures with Pascal, Lisp, or C language code. Similarly, anybody could pick any abstract-type-system for associating with variables. If you name a specific ADT approach, you restrict this range. e.g: When you pick Guttag's version, you push away Hoare's. Why? Where are the reasons listed? Where are any example type studies? And, where are the tools to introduce those ADTs to nets, the way NN73 (p.724) had discussed, how we could have alternatives in representation?
The named but omitted inclusion of Guttag's version of abstract data types, then, is only an absurd feature. It is only overspecifying, in this context. Whatever the data-representation may be, they are only somewhere behind some predicates, or "data-transfer specifications", which are heard of, but not seen in copycat82. There are no discussions in copycat82, about how the very separate formalisms would be inter-related (Petri nets, and algebraic data specification) - "except" naive displays of rectangle-partitioning, even which also have their shares of faults and/or omissions, as we will discuss.
Guttag, in that tutorial paper (on page 23), suggests that the type-system he studies, is preferrable for "a type abstraction that is not readily represented or modeled by a well-known type." As such, it is absurd, to find that copycat82 (over)specifies the particular type system, but next, does not present any type studies, whatsoever - let alone integrating with Petri nets.
In fact, it was the NN73 that included new abstractions such as a queue/stack with options to re-order (the Q-macro location), a resource-handler (RH-macro), and a few (extended) operators, Jn, Yn, etc. This was well-beyond the "Turing tar-pit" that Guttag refers to, I think. In fact, NN73, when presenting macros, for E-nets (on page 721), already state that, without macros, "if one is limited to these primitives, the resulting net ... complexity obscures function ... defeats one of the principal purposes of the development of E-nets." In other words, it is not a random co-incidence that, the Macro E-nets improve meaningfulness. That was the intention, from the start - with (xi,Psi) coupling, etc., and next, with macros. It is the point, beyond which, copycat82 cannot improve. In fact, copycat82 is not even there, when we observe its self-contradictions surface.
The false-suggestion, "why" specifically, the algebraic variety was proposed, is stated as its being "closer to the set theoretic nature of copycat82's design representation." (page 41, in copycat82). But this is not how Guttag differentiates its system, as contrasted to Hoare's. And it is not clear what copycat82 means, if anything. It is only a rush to introduce "some feature, whatsoever" it appears, and the feature was to be the naming of guttag's type-system, as an attention-diverting, false advertisement.
To oppose such an overspecification, by contra-position, I notice that, the Hoare approach could fit Petri nets, very well, too, (possibly even more fit) - if anybody would really take his/her time to study it. Here is an initial pointer: the Hoare-triplet very well fits the Petri net transition/subnet, with its in/out places. i.e:the three sets, in both cases, correspond to each other.
A bit more advanced pointers:
In other words, only mentioning Guttag's name, and his tutorial, is not any improvement, by itself. It could be a research question, if at least, we could tell what it was expected to improve, beyond the existing net studies. Not to mention that, a question has to be answered, too, before obtaining a Ph.D. degree.
For more about these, please read the pages: