It should be possible. If it's not set, the Android SDK will simply set it to the same value as Android Minimum Version.
It's really just a way for you to tell the device that you have tested up to the Target version and that it works the same as on the Minimum version, so if someone tries to use the app on a device newer than Target, some compatibility options might be turned on automatically to ensure function.
If the highest you've tested on is the same as Minimum, compatibility mode will always be turned on for newer versions of API.