I've never basted my turkey.  Always start breast side down, turn for last 45 minutes.  If I'm doing
a glaze, I WILL baste it with glaze every 10 minutes during the last 30 but that's not nearly as labor intensive as basting the entire time.  I can't remember ever turning out a dry bird.
I suppose that traditional presentation would be one good reason to cook breast side up which does require the baste-until-you-die method. Interestingly enough, by the end of the whole magillah, you'll qualify as a (wait for it. . . ) Master Baster.  Ahem.
By the way, if you have problems "flipping" your big-bird (I know, I know, I said "flipping the bird" get over it) when cooking it breast-side down. . . before putting the bird on its rack and starting to roast, make a sling out of foil which you've sprayed with oil.  Later, when you want to turn the bird, you just use the sling to flip it.