leaving comments aside and going back to topic:

as i'm currently in the process of building my own fan controller, i doing some math for selecting the correct output transistor.

the goal is to keep the power dissipated by the transitor in focus and not the total power the fan will use. if the fan is running at full speed (at 12V and draws about 1A) the transistor needs to be able to run the full current, but it will drop just something below 1V, thus needs to be able to dissipate less than 1W!

the story gets interesting when the fan is running at half speed which might be at 6V and in this situation the fan is drawing about 0,5A. you can see it coming: the transistor needs to drop 6V off the 12V supply to feed the requested 6V to the fan. at this time the transsitor dissipates about 6V x 0.5A = 3W.

as you can see, running the fan at full speed is not the point to take care of!

anyway, in any case we are far away from the advertised 20W, 30W or even 45W a fancontroller is able to control.

even the increased power draw during startup, should not be that much of a problem. its very likely the transistors used are able to handle a magnitude of the required current the fan will draw at startup. especially if you take into account, this will last just for fractions of a second in most cases.

this all holds true for so called linear voltage regulation!

coming now to your lamptron. as far as i know the lamptron is not utilizing linear voltage regulation but using PWN control instead. which most fancontrollers are as its the cheaper solution. when running in PWM mode, the transistor is by far NOT stressed as in linear mode. think of switching the fan on and off rapidly within a certain time interval, eg, 10sec: if you switch it on for 3sec and off for 7sec the fan will get only 30% of the energy it would get when it is switched on for 10 sec. thats pretty much what PWM control is about.
the transistor has to dissipate much less power as it is either switched off

current is 0A thus dissipated power is 0W

OR

switched on, where current might be 1A but voltage drop is far below 1V which gives a dissipated power of less than 1W

did some experiments with PWM control myself, but unfortunately the circuitry needs to be tuned for a certain powerrange of fans.it worked seemlesly with some fans but did not work at all with other fans. either the circuitry is designed to control standard case fans or it is designed to control powerhungry fans like some deltas, but it most likely wont be able to control both of them!

also the base frequency used in PWM control is an important factor. low base frequency let you control a wider range of fans, but has the disadvantage of generating this ticking and annoying sound and also prevents correct rpm readings at lower speeds.

to make a long story short:
powercapabilities of fancontrollers using PWM is more or less a marketing gag. if PWM is working as expected you want run into a problem here.

this is different for linear voltage control, but as stated above, the power used by fans is much overrated.

here is an example of a delta fan (the most powerhungry fan martinm210 recently tested. look at the figure:
fan voltage / dissipated power in the transsistor (linear voltage control)
5V / 1.7W
6V / 2.1W
7V / 2.2W
8V / 2.1W
9V / 1.9W
10V / 1.5W
11V / 1.0W
12V / 0.4W

as you can see, the most demanding range is 6V to 9V but the total power dissipated is still just above 2W and far away from the advertised limit of most fancontrollers.

the advantage of linear voltage control is, it will work for all fans without the problem of this ticking sound but at higher cost. also rpm readings will work almost the whole rpm range.

when you are in search of a fan controller i recommend to look for one which is not working in PWM mode.

will keep you posted somewhere on this forums how i proceed with my own project and findings regarding fan control.