As the author of the offending fusion question, I apologize for anything that resulted from this. In fact, I may have been the moderator responsible for giving 15 points, because I saw the contradiction in the question, but should have realized that the uniquely identifying device clue earlier trumped the end. (When this question came up, I went to the stat room and told them what I had done, and they did not object) The question should have ended possibly with some clue about ITER, but I'm not sure if I originally wrote the "contrasting with fission" part. I may have.
As to the errors in the question, I did attempt to confirm with sources other than wikipedia. I believe the inequality/product distinction, while true, not a gigantic mistake. A criterion by its nature implies some sort of threshold value which the product is to reach. And as to the fusion temperature, numerous sources mention the triple product as a measure of merit for tokamaks. I assumed that it was a more accurate measurement than simply the Lawson product. If I'm wrong as you say, I stand correted and defer to your expertise.
For the ignition definition, here was the source I used.
http://fusedweb.pppl.gov/FAQ/section1-physics.txt
(Lawrence Livermore National Labs I figured would be reputable enough)
Fusion Physics FAQ wrote:
L. Just how hot and confined do these plasmas need to be?
(Or, what conditions are needed for controlled fusion?)
Basically, the hotter your plasma, the more fusion you will have,
because the more ions will be flying around fast enough to stick
together. (Although actually you can go *too* fast, and the atoms
then start to whiz by too quickly, and don't stick together long
enough to fuse properly. This limit is not usually achieved in
practice.) The more dense your plasma is, the more ions there are
in a small space, and the more collisions you are likely to have.
Finally, the longer you can keep your plasma hot, the more likely
it is that something will fuse, so duration is important too. More
importantly, the slower your plasma loses energy, the more likely
it is that it will be able to sustain its temperature from internal
fusion reactions, and "ignite." The ratio of fusion energy
production to plasma energy loss is what really counts here.
Hotness is measured by temperature, and as explained above, the
D-T fuel cycle (the easiest) requires temperatures of about 10 keV,
or 100,000,000 degrees kelvin. Density is typically measured in
particles-per-cubic centimeter or particles-per-cubic meter.
The required density depends on the confinement duration.
The Lawson product, defined as (density)*(confinement time) is a
key measure of plasma confinement, and determines what
combinations of density and energy confinement will give you
fusion at a given temperature. It is important to note that
what you must confine is the *energy* (thermal energy) stored
in the plasma, and not necessarily the plasma particles.
There's a lot of subtlety here; for instance, you want to
confine your fuel ions as well as their energy, so that they
stick around and fuse, but you *don't* want to confine the
"ash" from the reactions, because the ash needs to get out
of the reactor... But you'd like to get the *energy*
out of the ash to keep your fuel hot so it will fuse better!
(And it gets even more complicated than that!)
Regardless, it's true that for a special value of the Lawson
product, the fusion power produced in your plasma will just
balance the energy losses as energy in the plasma becomes
unconfined, and *ignition* occurs. That is, as long as
the plasma fuel stays around, the plasma will keep itself
hot enough to keep fusing.
In conclusion, the ending of the question deserves scorn, but I attempted to verify the other clues with numerous non-wikipedia sources.