A thought on Anglo-Catholicism
I mentioned before here I would like to do a website with the different ceremonial styles in Anglicanism, and in studying and reading to do so I think I realized one reason why Anglo-Catholicism seems to be so difficult to perfectly incapsulate and describe, or seems to be the subject of disagreement: the nature of the Catholicism in Anglo-Catholicism. I am not an expert but here is a thought I have had.
For example, those modern folks who look back at the robust tradition of Old High Churchmanship (OHC) in the Laudian vein, which runs through the Caroline Divines, might view it as Anglo-Catholic, although the OHC would've called it via media. These people tended to be focused on drawing on pre-Reformation English Catholic tradition, and saw their concept of via media as the "best of both worlds," still firmly Protestant but committed to specifically English Christian tradition, even if Catholic. Interestingly, the Puritans in CoE certainly would've called them Catholic.
The Oxford Movement/Tractarians, who were engaged in a Catholic revival in England (and at odds with the OHC!) and would've certainly seen themselves as Anglo-Catholic (so much so that many of them defected to the RC), were also trying to recover English Catholicism but (it seems to me) were usually reference existing Tridentine forms and the Catholicism that was a product of the Counter-Reformation. As a result, their practice was more akin to their Catholic contemporaries than the OHC, or they at least would've viewed older liturgical modes through a tridentine lens.
These two traditions were really engaged in a dialogue and produce a certain set of styles or views of Anglo-Catholicism in the 20th century that we might see evident in the works of ECR Lamburn or Percy Dearmer. In places like the US, of course, Anglo-Catholicism would continue to develop alongside the post-Vatican I changes of the RC.
Finally, we have more modern Anglo-Catholicism in Anglicanism, which itself appears to be a product of the late-20th century Liturgical movement and the changes in the RC brought about by Vatican II.
This means, in essence, Anglo-Catholicism has had multiple phases (undivided from RC, OHC, Oxford movement, Lamburn-ish, Modern) which has been in dialogue with changes in Catholicism and Protestantism, as well as historical studies and inter-Anglican debates, and so what emerges is, to my mind, a tradition that is very stable on the "Anglo-" end but in constant flux and discussion on the -Catholicism end.
EDIT: This is, shockingly, biased towards USA and England and not necessarily elsewhere.