RE: Getting the shaft under your eye
The guys who have mentioned canting with a longbow are spot on. If you havent read Fergusons book yet, do so. He goes into detail on the subject of shooting left. Asbell's 2nd book also goes into some good detail on longbow vs recurve shooting. JHansen's comment on shelf heigth again was referencing canting of the bow and the effects the distance between the arrow and the shelf and your hand placement will have.
I would not give up the groove for the tips ever again. Reason being, I plan on doing this for years to come and not succumb to tendonities in my fingers when a simple anchor point adjustment would alieviate all of this. Learn to relax your hand and you wont have to get out "on your tips" if you will.
On the below the eye, here's my thoughts. Whether you are stincter, gapper, split vision'er, or whatever, everything rely's on line of site. With the PROPER set of arrows out of a longbow, spine and tuned, you are more apt to hit things if you are pointed at them to start with. Like hunting any animal, the easier it is for them to get to you (speaking of calling here), the more likely they are to come eh. Well shooting is no different. The less you have to make your thinker work, the more it's going to work for you. Meaning if you naturally are coming to a point where you dont have to (mentally or otherwise) make adjustments however minute, the ONLY deviation you'll have will be up and down. The more natural things are going to work out for you, and the better shot you will be EASIER with less WORK and you will be able tomaintain this with less headaches along with being able to shoot many different bows with better then average accuracy without ever having shot them before.
There are a ton of factors why people shoot left. The more you can line up from tip of arrow to head position, to elbow alignment, to feet and everything inbetween, the more likely you are to hit what you are looking at.
Many will talk about the arrow, when properly spined, will wrap around the bow. It's ironic in one of Hills older books referencing his split vision technique his aiming point was to the RIGHT of where he wanted to hit. Mind you I believe this was printed before he was shooting with a more modern cut in riser as all references to bows and photo's included in the book are of him with more primitive looking bows.
Just my buck50