I found a bug in the thermal washer that I was able to replicate in the rotary maceraor by making it have multiple outputs in one of the recipes:

{
	"input": {
		"tag": "forge:ores/iron",
		"size": 1,
		"type": "ic2:tag"
	},
	"output": {
		"xp": 0.7,
		"outputs": [
			{
				"item": "ic2c_extras:crushed_iron_ore",
				"size": 2,
				"type": "ic2:nbt"
			},
			{
				"item": "ic2:dust_iron",
				"size": 1,
				"type": "ic2:nbt"
			}
		],
		"type": "ic2:simple"
	}
}

Note: the recipe outputs must differ in amounts.
seems to be caused by the output queue still containing items in it.

@Trinsdar technically this intended behavior.
Since the machine checks if it can work and not if it can operate.
(Can work => valid recipe + has energy, while can operate means that it actually can increase the progressbar)

Though I can see why you see that as a bug.

I don't plan to change this behavior.
But if you want to fix this yourself.
Simply override the pre tick function which has 3 parameters.
HasRecipe, CanWork, CanOperate.

That logic is simply there just for adv machines :)