I guess we are blessed with many rigging options. As chh said, it depends. A double bowline is another option. It has most of the advantages of the double 8 but uses less rope.
A brief defense of the butterfly/8 Y-hang(which is more often a butterfly/butterfly since there is often a traverse line involved):
chh wrote: First, I think it looks sloppy. This is an aesthetic thing and totally subjective.
I can't argue with your sense of aesthetics. I don't find the Butterfly/8 particularly heinous, but I would also note that aesthetics are not my primary concern when rigging so I haven't thought too much about it.
chh wrote:Second, as has been said, rig around your rub points....geez!
I am not sure I understand you here. I often rig around rub points using a butterfly/8 Y-hang. In fact if the information in this thread is correct a butterfly/8 is more effective at this, since it allows you to position the rope anywhere on the plane between your two anchors. Whereas it seems a double eight will slowly equalize until it lies directly between the two points? Granted the more you move the rope towards one anchor with a butterfly/8 the less equal the load sharing. But at least you have the option.
chh wrote:Third, if it's the anchor points and not the rub/cutting points that are the issue, there are much more eloquent ways of load sharing that you may or may not be able to achieve with what you have with you.
There are certainly a variety of ways to rig a load sharing or load equalizing anchor. Eloquence is also a pretty subjective term. But using less rope(than a double eight) and not having to carry any extra stuff for other set ups seems pretty eloquent to me. I don't know of any more eloquent load-sharing anchors personally. I do know of more eloquent load-equalizing anchors. But in most situations I can pre-equalize(or close enough) my butterfly/8 and not have to worry about extension and therefore shock loading that occurs in load equalizing set ups. And since the direction of pull is almost always constant I don't really need an anchor that is dynamically equalizing.
One downside of a butterfly/8 or butterfly/butterfly is that people have to know not to clip into the single strand leg of the rigging since doing so typically places you on just one bolt. Also, as I stated before, double eights are superior to butterfly/butterfly when you need the traverse line that approaches the pitch head to head straight for the knot on your Y-hang rigging. This is often the case if the pitch head is far from walls. I can also think of situations where a fall on a traverse line approaching the y-hang would generate higher shock loads if the rigging was a butterfly/butterfly versus a double eight.
Again, options and it depends. Both ways of rigging are safe and have their place.