Are their many instances where an Alzheimer's patient dies without going through end-stage symptoms?

That's an excellent question. I would like to know more about this.

I suppose it depends on the type of dementia. I've read that conditions that cause dementia that are NOT Alzheimers, may not cause the standard Stages that we often see associated with dementia's progress. However, I have seen those standard stages with some patients who have conditions like Vascular Dementia.

I know of a couple of people who had Rapidly Progressing Dementia, (I think that's the technical name. ) who died within a year or two of diagnosis. This came after extremely fast mental decline. These were young people and in their 40's, though, I don't think it's very common.

I have seen here and other places where a person lost their LO with dementia, but, they never lost the ability to eat, smile, talk or even walk. So, I suppose that it does happen. With my LO I have noticed that she has on a Stepped down scale, lost abilities.  She has lived past the time that most people with VD live, if I believe the statistics.  

My boss' wife had Alzheimer's for 15 years and she wasn't bedridden, and she still knew who her husband was and one long time caregiver. The wife was on Hospice Care but she went out to the stores with her husband, go for walks with him, etc. Out of the blue one day she passed and the cause was Alzheimer's.

As for incontinence, that can happen to anyone at any time, they don't need to have Alzheimer's. It's pretty much just a fact of life when one gets older.