Personally, I think that whether the roots are on the lean side or opposite to it, is neither here nor there. It all comes down to the individual tree, personal taste and nature itself.
If every semi cascade or slanting style trees, all had the nebari on one side or the other, wouldn't it be rather boring? Both Al and Will have presented very beautiful examples of both. So I fail to see what this arguement is achieving, other than hostility, resentment and almost school yard like bickering. So unless you both want a spanking and sent to bed with no supper - behave!
Surely the one thing that should be learnt here, is that BOTH examples will be found in nature, and that bringing out the hidden beauty in each tree should be the most important factor.
Regards,
Aaron