Face to face: Trike vs. standard bike on expedition

Hi,

I do loaded touring on my regular standard bike (sitting upright,
Brooks saddle, Aero bar) using panniers.
I'm interested in buying a tadpole trike for my next "expedition" being
roughly 4000 mi/6000 km. I'm not interested in recumbents - only
trikes.
My main reason for buying a trike would be the speed increase. But
browsing various forums and newsgroups it turns out that the speed
picture is different.
So I have a question for those who ride both a trike and a regular
bike: Without talking about weight, rolling resistance etc, I would
like to know if you go faster on a trike (with or without panniers).

On my loaded touring bike I go 125mi/200km a day, even in mountains
like the Rockies. Usually I'm only limited by the daylight hours. I
average at 15 mph/24kmh.
I know it's a bit extreme, but it would be cool to go even faster.
Feeling that my power is used efficiently is VERY important to me -
this is why I don't have any bike generators (like the ones in the
front hub) or internal gear hub systems on my touring bike.

I know recumbents and trikes call for a much more relaxed driving style
which eliminates soar etc. But if I ride from dusk til dawn on my
regular touring bike (and not biking when it's dark) I do those 125 mi
averaging 15 mph (loaded with 35 pounds of gear) and that's it. The
values are, of course, without hourly brakes, eating, shopping etc. If
I cannot go faster/longer I will not buy a trike. This is crucial.

I must admit that I'm the stamina type of rider - I don't like to waste
excess energy because I know the wind resistance is squared, so I ride
at 15 mph but for a LONG time. I would adapt this riding style to the
trike.

On my regular bike I usually bike 1 hour, make a 10 min break, ride one
hour, 10 min break, at noon shopping, eating for 1 hour and so forth.
I'm only making breaks to give my butt some rest (it might irritate a
bit) and eating snacks. So, if I could eat snacks while riding the
trike, because I would't get soar at all anymore - it would of course
be interesting.

So what are the experts saying? Can I gain 1-2 mph compared to a
standard bike (we're talking loaded bikes here)?

Thanks in advance, Lucas Jensen