On Foucault's account, power doesn't work through a large-scale finality, a closed teleology, or a centralized organizing principle. On the contrary, power is deployed through a series of local, diffuse, and everyday practices. Accordingly, for Foucault, our discourses are manifestations and enactments of an omnipresent discourse-power complex. Probably, that is why he said: "My point is not that everything is bad, but that everything is dangerous, which is not exactly the same as bad. If everything is dangerous, then we always have something to do. So, my position leads not to apathy but to a hyper- and pessimistic activism. I think that the ethico-political choice we have to make every day is to determine which is the main danger".

if we "always have something to do", does it not become imperative to control all aspects of discourse, everywhere? In which case how can we avoid legitimizing our own particular use of "violence"? If discourse is violence would it not be better to remain silent? — PuerAzaelis

The implicit connection of our discourse to power should not be simply interpreted as "violence". After all, it is impossible to control all aspects of discourse or
to stay completely silent. Foucault's own choice was an attempt to extend, broaden, or saturate specific effects and social presuppositions within a given field while trying to downplay or limit others.

If discourse is violence would it not be better to remain silent? — PuerAzaelis

According to Foucault:

Power is strength over someone.
Not all power is violence. We must distinguish power from domination which institutionalizes power and leads it to violence.
Discourse is not the only form of power. Every social structure implies power. Therefore, there is no point in keeping quiet.
Every human relationship implies power. The absence of power is a utopia. What we have to do is oppose counter-power to the power of domination.

Note that for Foucault power is not bad in itself : it can be creative and a form of rebellion against domination.

I doubt that it's a falsifiable theory. After all, it's philosophy.