Completely. BT is a natural bacteria that is deadly to caterpillars who ingest it. Safers Insect Killing Soap Spray is potassium salts of fatty acids, which kills soft-bodied bugs on contact (aphids, mites, thrips, whiteflies) and doesn't work when it's dry. It will accumulate on the leaves and flowers which is why the it comes with the instructions to rinse after it dries:Thought so! Is safer different?
"Do not make repeated sprays at short intervals without thoroughly rinsing foliage."
We're not allowed to link to pdf files here, so here is the link without the .pdf at the end. Feel free to add it back if you'd like to read them: