I think it illustrates how "elliptical" is hard to quantify meaningfully.
Del, you bring out a good point, that a method such as using ellipses in paint, in order to judge correct tiller, needs to be quantified. I actually do quantify, in my own notes, the ellipses I use when tillering my own bows. I would need to build a few more with different tillers, and do some comparative shooting, before I could offer any specific suggestion or recommendations.
No one actually has ever defined how elliptical the ellipse should be and that's my big beef with the whole thing! 
Of course , if one wishes to replicate a Mary Rose warbow tiller shape, that would need to be defined somehow. Just out of curiousity, has anyone seen any study done on the differences between the bows found on the ship (regarding profiles and expected tiller shape)?
Having taken a second look at the pic I posted, I realize that it is not very becoming of Bob's nice workmanship, and will let your more well fitted drawing serve as an example of the usefulness of paint.
