I think Redhawk gave top notch answers. Chemical fertilizers do not have much place in a permaculture setting. In permeculture value is given the varied uses or long term benefits of an application, not immediate results. It is more about resilience than efficiency. Chems are for 100% efficiency (if you define efficiency as return of invested money- only money). Also it can be answer to 2% of issues of the problems we are facing (alfalfa can solve say 10-15%), and chems have many alternatives. Enough with purple.
Lets assume you want to build a compost pile. You will use leaves, grass clippings, manure, coffee grounds and such, right? Maybe something unusual, like a ton of chicken legs. You will need to check the internet but still you can calculate green/brown ratio and get it cooking. What if you use something processed, such as dog food? It has ash, corn and a lot of preservative stuff, but mainly meat and bone and thing like that. We don't know the NPK values of dog/cat food dog food as fertilizer
but you can still predict the outcome. If you use dog food as fertilizer, you will have bigger tomatoes. Okay, that is also fine. Lets assume you will use something way more processed, such as Pringles, candies, coke(maybe?) and such. Do we have a use for coke in a permaculture setting? Can we use it instead of molasses or fertilizer? It gets complicated and thus harder to predict (for chems things like inert materials, compounds for slow release etc). You can draw a similar picture with chemical fertilizers. Similar questions are asked before: one of them is Upcycle: chemical fertilizer
I haven't uploaded my findings yet. I used chems on dirt, works wonderful. Frankly I would not be able to harvest even tomato leaves without it. I used it on living soil, it made a difference in the first year, as if I turned on the turbo mode. But I know it is going to kill the soil. Over 10 year of heavy use of chems and -cides is what turned my land into a hard rock clay. For another try, I added it to my compost piles while building it, not much difference at all. It heated up and cooled down as usual. It didn't make a significant increase of harvests either. This year I added chems to compost pile in its final turn, not while building it. That pile is acting weird. It is heating up, cooling down, heating up again, cooling down to 20C. Then, all of a sudden, heating up 35C. I don't know what the hell is going on in there. The twin compost pile (with no chems) heated up to 30C's after its final turn and cooled down to 14C. Same materials, same environment, same watering but acting very different. This weirdness did not showed up if it was added initially.
So back to your question Nathan, unless you don't have alternatives, do not use it. If you are going to use it, use it in a diluted way as Dr Redhawk said. Try to use simple chem products. I thought slow release chems might be less harmful to soil, but my compost pile is acting suggestively different. It is hard to build healthy soil. If you start with dirt, nothing to kill, you are free. I do not recommend to risk of killing your soil though.