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Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
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I'll admit to a vast amount of study but a minimal ability to explain my thoughts about steering geometry and load carrying. I have always liked the handling of a long (6-6.5cm) trail bike. I can't really say why but they just feel nicer to my manors of riding. I read VBQ and take issue with what Jan writes (his latest tandem article hits so many wrong buttons IME...) but I do respect his attempts to make sense and explain things.
So what do I feel about CG and leverage?
I like my front load to be low and behind the steering axis. My touring bikes all handle nicer w/out a handle bar bag and with low rider panniers. (but I do use a handle bar bag on tours. Just another example of balancing needs against abilities). I like a rear ward weight bias with a camping tour bike. It's hard to carry all the gear with a front bias when you're hauling 70+ lbs of stuff. So a low and rear biased CG is my choice.
As to leverage- I've thought that a greater trail means that the side/steering forces have to travel further to make the same amount of steering angle change. My rear weight bias has the "tail wagging the dog" nature and minimizing the steering effects of such seems to work for me. (And this is born out on the tandems I have owned and test ridden. For an experienced team a long trail bike handles nicer then a short trail tandem. The experienced stoked doesn't provoke the stoker steer that a newbie does and the more single bike handling nature of the long trail tandem often is preferred by the experienced team).
When I first started building frames I read everything I could on design including some of a series of articles (Mullett's Mechanics) from a British magazine. Is proposed the wheel flop (or the frame raise/drop) theory as to certain handling aspects. Later reading of Jim Papadopoulos et all's research the lever arm/trail aspects seemed to make more sense (although I won't begin to say I followed their math).
Granted this is a bit of a tangent from the OP's question of front end loaded situations. But it's what I have played with for a long time. Andy.