So, the idea of something being inevitable is something that is more due our society (a science obsessed and mathmatically driven soceity) that has things go from a + b = c. Things are rarely ever this way in history as many things hinge on larger trends, a series of often disconnected events, or small things.

The French Revolution starts for two reasons, larger trends of royal spending and a small, and inconsequential event.

The Estates General was called in 1789, the first time in a hundred and we very give years, because of a debt crisis. After many ministers and a failed attempt to reform France's finances, Louis XVI was looking for ways to relieve the French debt that was threatening the Crown with bankruptcy. This debt was a long held debt, first started under Louis XIV to finance the various wars of expansion that brought France to the Rhine and "her natural frontiers" of the Alps, Pyrenees, and the Rhine. This would be extended to Louis XV, a mediocre ruler that continued wars on credit, such as the War of the Austrian Succession and the French & Indian/Seven Years War, both failures for France. On top of this, Louis XVI would inherit the debt and add to it in a proxy war against the British in the Americas.

And this is why the Estates General was called. There was interest in trying to find new ways to tax the nobility, as the Third Estate was already highly taxed. However, there was a problem, the Third Estate (the peasantry and middle class) out numbered the First and Second Estates (the Clergy and the Nobility respectively) and it the Estates General would vote via headcount, the Third Estate would win any vote they wished. As such, the Second Estate worked and tried to argue in favor of voting by bloc, as each estate would vote by Estate not by head. With the Third Estate refusing to do this, they were locked out of the meeting hall and met in a near by Tennis Court.

So, with this you have two things happening, a disagreement about parliamentary procedure resulting from a debt crisis of the Crown. A big trend of Crown spending meeting a tiny event like procedure.

There is a reason why theory tends to fail the Revolution. It doesn't fit a specific thought pattern or history pattern of before or after. The Revolution is an anomaly in history, which is why it's still so highly discussed and written about.

Sources:

Contesting the French Revolution by Paul R. Hanson

A reply to /u/fishmonkey123

The French Revolution is very well studied and well discussed, if you think that it was not inevitable, then feel free to post your arguments as to why it was so or not so, and we can have a discussion in this thread.

mostly because every involved party from peasantry to bourgeoisie to nobility to monarchy showed a certain sense of inconsistency and almost ambivalence

I'm not sure what you're getting at here. Any labeling of groups of people into "peasantry" and "bourgeoisie" and "nobility" is bound to introduce errors that lead to inconsistency in interest, opinion, action. So I don't think this is useful. In fact, I was discussing with /u/DonaldFDraper that the opening of the Estates-General of 1789 reflected this quite strongly, whether each estate hold votes first (akin to a primary system) or they should all vote together. It's not a matter of strength of each vote, but also the issue of how each estate had disparate interests.

Going back a little bit to the period of Louis XIV and in particular of the Fronde, we saw disagreements between the royal power and the sum of nobles, princes, and parlements in terms of how they should interact with each other and what privileges and liberties they had. In the past, what tended to happen was that when the royal needed help from the parlement or estates general, they received that help in return for further privileges or gifts to the members of that body. Of course, there were notable instances where this led to war and in the case of victory for the royal there was significant curtailment of privileges. In particular, his victory at the Fronde allowed Louis XIV to turn princes and nobles from regional powers into a new system of aristocracy. But it took the two Frondes to achieve this new alignment. What is important here is that we have to think about systems of government that aligned its constituent estates. Freed from the restraints of nobles and parlement, Louis XIV no longer had need for the Estates General; its last meeting was in 1614 under Louis XIII. Further, the first estates the clergy had been largely in alignment with the second estates, after centuries of religious warfare and royal control of religious matters. That meant that royals counted on the first and second estates to support them reliably.

Going back to 1789, we saw the same question again. Louis XVI summoned the Estates General due to financial crises. This was over 150 years after the last time there was such as a meeting. What became clear was that this ancient (literally) institution and arrangement was sorely lacking, in particular highlighting the interest of the third estate. The second estate also looked for opportunities to empower themselves, to re-obtain their ancient privileges.

So if you are to argue that the French Revolution was inevitable, you have to give an argument of what things needed to change in order to avoid it. I look forward to your argument.

You say you have read some of William Doyle's work - I was wondering if that included Aristocracy and its Enemies in the Age of Revolution? It's a more recent publication and I found it particularly useful for tracing the genesis of the increasing attacks on nobility leading up to the revolution (I know your question focuses on 1789, but this takes it both back a bit further and forward a bit more). There's a particularly interesting chapter on the American Society of the Cincinnati and the impact that the establishment of what detractors saw as an attempt to establish a quasi-nobility on the fledgling American Republican had on French society also. The Comte de Mirabeau actually publishes a pamphlet on the issue in French and in France in 1785. The fact that a pamphlet attacking heredity in general can be published in France, clandestinely or not, shows that there at least concerns over the legitimacy of hereditary honours before the revolution even begins.