Family History and Family Mythology: Irish Version

No doubt this is an issue that crops up for family historians researching ancestors from any number of ethnic backgrounds and national origins. But I suspect the problem is especially prevalent in Irish genealogy, where the attempt to apply evidence-based methods typically involves cutting through vast areas long since overgrown by dense thickets of mythology. 
The problem goes something like this: If you’re looking for ancestors of Irish origin, you’ll probably have at least a few people in your family who want you to discover that, back in the mists of time (that glorious, golden age) our ancestors were amongst the kings and queens of the Emerald Isle; instead, you have to tell them that, as best you can make out and as far back as you can go, it looks like our ancestors were amongst the agrarian underclass of County Tipperary. Okay, that’s a bit of an exaggeration, admittedly. And for the most part, probably, the poorest of the poor didn’t emigrate to Canada, because emigration did require some means (the ability to book passage on a ship, in the first place). But substitute “landed gentry” for “kings and queens,” and “poor tenant-farmers” for “agrarian underclass,” and I think it’s a pretty fair characterization.

Well, it can be a little bit uncomfortable. Do you really want to disabuse an elderly great-aunt, say, of some wrongly held but warmly cherished belief if it means sacrificing an important part of her self-identity on the altar of accuracy in genealogy? Well, in some cases I don’t, frankly. I mean, I certainly don’t want to add to the confusion and inaccuracy, or to actively support an interpretation that I know to be wrong or misguided. But I have to confess that I’m not always inclined toward an energetic debunking of family myth, either (depending, of course, on the context, which is to say, depending, often, on who it is who has asked me something or other about our family’s history).
So I’m not going to subject my great-aunt to a tedious lecture on why I think that family coat of arms she has emblazoned on a tea towel is basically bogus; but at the same time, I’m not going to adorn my family history pages with a coat of arms that I believe to be a dubious artifact of the genealogical-tourism industry either. I guess I hope that my non-use of the coat of arms will speak for itself (which it probably won’t, in some many most cases).
Anyway, my own interpretation of our family history is just that: my own interpretation. I’m trying to ground it in trustworthy sources, and to back it up with reference to reliable authorities; but at the end of the day it’s my own version, and someone else in my family might look at and rely upon the same evidence and yet come out with a different version entirely. And in debunking certain family myths in the creation of my own account of our family’s history, who knows when or where I might be guilty of constructing a new, counter-mythic mythology?