That period was much less transparent than nowadays, that's also a factor
A "factor" yes but there has certainly been a "sea change" in the way in which the WHC operates both in relation to the ABs and internally as between its members.
Assif has chosen 1995 as a convenient dividing point which is fair enough. It would certainly be "nice" to be able to see "Disagreement" events by year but that could be difficult?
I have had a look at the very early years up to 1985 and, whilst it is possible that there was great turmoil at the WHCs unbeknown to us I get the impression that we probably do know where the issues were and they tended to be about "suitability of subject" and "international disputes" rather than OUV, comparability, completeness of documentation etc etc ie about matters like Auschwitz and Jerusalem rather than about Khor Dubai and Naumburg
In those days the "Bureau" met before the WHC and went through the list of nominations making its proposals to the WHC. It is very noticeable just how many nominations are completely "rejected" without, apparently, much dissension - the AB evaluations were largely just accepted. Why?
a. I suspect that in those early days the members of the WHC were less "career diplomats" whose job it is to "fight" (diplomatically of course) for their country's benefit and more people genuinely interested in Culture/Nature etc and therefore far more willing to accept the recommendations of the AB.
b. That also reflects the fact that governments hadn't yet cottoned on to how "valuable" an inscription was on a range of factors - economic, national pride, demonstration that the government was actually achieving something etc etc!! Conversely of course the effort/money spent in preparing a nomination was significantly lower than now. No one was in the situation of that spokesman for Nimes which had banked millions of Euro on a development strategy, building iconic musea etc of which a successful inscription was a major plank! No wonder he was angry - "We have spent all that money and now you tell us we aren't going to get inscribed - how dare you!!!"
c. There were also of course fewer countries involved and the composition of the WHC was less determined by region etc so the sort of cabals which can now band together to achieve unjustifiable inscriptions were less likely.
d. Everyone was feeling there way a bit knowing that case law was being established and not quite sure where they were going with the whole thing. I found this report from 1983 ( http://whc.unesco.org/archive/1983/sc-83-conf009-inf2e.pdf
) when there were 150 WHS discussing the whole issue of ensuring consistency and dealing with situations they hadn't foreseen. Interesting to note that the mere idea of inscribing an entire "City" seems to have come as a bit of a surprise when the original "idea" had been to inscribe "monuments" and "sites". The concern was more about the nominations which were being rejected than in the ones which were getting through. Also that the idea of having a T List was primarily to help set the "standard" against which to evaluate nomination knowing the range of similar sites which were around - it certainly hasn't turned out that way!!
I look at Hildesheim Cathedral which is mentioned in the report as having possibly been "unfairly treated" in comparison with Speyer - rejected in 1982 by the Bureau and not even considered at the WHC. Not a murmour, as far as we know, from Germany. Compare that with the forces mobilised to get Naumburg cathedral over the line in 2018!!! Mind you - it was presented again in 1985 and I just love the ICOMOS grovelling comment in its evaluation "ICOMOS, which after having, in 1982, voiced serious reservations as to the form of the proposal for the inclusion of Hildesheim on the World Heritage List, expresses its unmitigated agreement with the new nomination"!!!