Hiding your logic from clients is overrated. If that's all you're selling them with the software, you're not providing much service. Don't forget that you schema, the code oyu use, etc. is subject to copyright. clients can't just copy it and use it.

Most clients will never decrypt the procedures, heck most of them don't care. That's why they're buying your software. They don't have the time or inclination to write it themselves.