Is it safe for me to spray something in there

Maybe yes, maybe no.

Research very carefully. One of the things you have to find out is whether the product is "sensor safe". You can wreck your O2 sensors in short order by running the wrong chemical past them.

For example, in Alaska we attach heating pads to the oil pans of our engines, so at night we can plug the car in and keep the oil warm. These pads are attached with RTV silicone, and it is important to buy the product that is listed as being Sensor Safe. The non-safe fumes (smells like vinegar. Acetic acid?) from "regular" RTV silicone as it cures can get sucked into the air intake and damage the O2 sensors.

I wouldn't worry too much about "dislodge large amounts of that black crud," since there really isn't very much of it in that throttle body, it is apparently pretty soft (you can wipe it off with a rag) and you'd be surprised at just how much stuff your engine can ingest and spit out the exhaust without damage.

Be glad your sticking throttle butterfly is not the same one that the Ford Taurus has. In that case, the butterfly valve actually wears a groove in the throttle body housing. Only known remedy is to replace the entire throttle body assembly, at a cost of about $600 if memory serves me correctly.

tanstaafl.