Originally Posted by
LastKraftWagen
LastKraft,
I am guessing of course, but I think in his configuration, the outer chain ring is removed and replaced with a timing belt pulley. I am also curious about the chain rings. I thought about doing the same, but was dissuaded by the specs which also called for a minimum 50t outer ring. I guess the code is "what you'd call guidelines than actual rules."
Where I live, there are no hills, so I'm never in the granny. But when we travel, we cannot do without. So eventually I will need to switch to the compact crank, but for now I will just experiment with the 39/52 outer rings. Regardless if the routing is internal or external, I still will need that extended derailleur clamp.
I'm actually considering DaVinci cranks with the swappable spyders. Then (if it all will work) I could swap between standard 53-39 and 50-34 for the hills. If the FD works okay with even smaller rings I may also consider the smallest spyder (MTB rings?). If I've thought it out right, it would be a simple spyder and chain swap and sliding the FD clamp up or down....Of course, best laid plans and all. 
Another albeit expensive option is the Lightning Cranks that also have a interchangeable spider. They have a simple solution to achieve the correct chain line as they have a spacer that goes in the spindle connection to widen the crank spindle length. We have not had any issues with these cranks and they are very light. It is easy to change out the spider however we have been satisfied with compact and 11-36 at this point.