You would need to modify it to install apps in a different way and to also sign them, and most things would not work due to root access being required, but technically you certainly can.
It should go without saying that the whole point of installing an app is that it work. It does me little good to have the binary sitting in the file system if it doesn't actually perform the function which it was built to perform.
Developer certs != jailbreak. Apple could provide a jailbreak option, but it chooses not to, so people who want to actually control their own devices (a not unreasonable thing for someone to want IMHO) have to deal with Chinese hackers.
