It seems like the most recent Android 4.2 has introduced this error condition on installation when one attempts to install an APK with a lower version. In prior versions of Android, one would be able to install older APK's simply via adb install -r <link to APK>. For debugging purposes, I frequently need to re-test older APK's; and the -r flag would replace the older build in older Android versions. Is there a work-around here to ignore [INSTALL_FAILED_VERSION_DOWNGRADE]?
It appears the latest version of adb tools has an "allow downgrade flag" that isn't shown in the adb help, but it is shown in the "pm" help on the device. So use:
adb install -r -d <link to apk>