If we are talking about "bumps" as being revolutions then I have a couple of choices. I see a revolution as being something that completely changes the "rules" of combat. My own test is that would a general from a previous era recognize the extant tactics. I think that there were two early revolutions that happened rather close to each other. The first was having some form of close-order drill and the second was the use of horses. Homeric epic poetry aside, war was changing (in those societies that employed these techniques) from single or tribal combat into battles between mass armies where group cohesion meant more than individual skill in battle.
The army that kept its nerve and stuck together despite the odds could prevail. Discipline, bravery, keeping ranks and the ability to execute drill under great duress could make all the difference.
I think that war trundled on until about 1900 to 1904 along those same lines. Armies would fight in relatively compact lines. Cavalry use had waxed and waned over the centuries and indeed by the US Civil War was not really the shock arm that it had occasionally evolved into. Nevertheless, I think that Alexander would have recognized Waterloo or Gettysburg as being battles he could fight. Indeed, I think that his army could have done quite well with a quick one-week course on firearms.
I haven't called gunpowder a revolution and that is a calculated risk as opposed to an oversight. Cannon, perhaps, could be seen as being revolutionary in what they did to seige warfare, but in a general sense battles fought in the late 18th century were fought much as they were centuries before. True rifles may have been the fore-runners of the upcoming Firepower Revolution.
The British gained a glimpse of the revolution in the Boer War, and the whole world saw it in Manchuria in 1904. Machine guns, barbed wire, trenches and quick-firing artillery meant that the old virtues of bravery and discipline under fire could be turned into deadly vices. (I didn't fully undestand what quick-firing artillery was and why the 1904 observers were so exicted. The recoil mechanisms that we take for granted had only recently been introduced and guns were now much more accurate as well as being able to fire more rapidly). I don't know if barbed wire and trenches should be seen as revolutionary but perhaps as adaptations to the machine guns and quick firing artillery.
The Japanese eventually abandoned their Prussian field regulations (their doctrine) and blue uniforms and went to dull uniforms and skirmish lines. Siege guns were used to pound fortifications instead of charges on foot (the Germans took notice of that) and cavalry didn't have much too do, much to the disappointment of the visiting Cavalry attaches. A visit to the front at Mukden revealed the nature of "the empty battlefield" where infiltration and trench lines replaced the formed up ranks of previous generations. British observers were gratified to see that their decisions from the Boer War had been validated, while French observers drew that the "offensive spirit" of the Japanese had allowed them to break through the stalemate against the passive Russians. The results of the latter analysis played themselves out tragically in WWI.
I would argue that this revolutionary doctrinal earthquake continued through to 1918. The integration of tanks, artillery, infantry and airpower backed by a modern logistical network was realized and put into practice. World War II took the methods of 1918 and refined them or evolved them to greter degree.
I would argue that we are still waiting for the next revolution. Our doctrine is actually pretty good at being descriptive. Doctrine, however, has problems being predictive about changes. It is hard to read future technologies and how emerging technologies will influence our business. If changes in technology are only really evolutionary then the extant proven doctrine should generally prevail. If, however, the technology is truly revolutionary then doctrine should be discarded. The trick is telling the difference.
