How do you keep the software locked in? The first thing you loose is TPS settings when you disconnect the battery. On the systems we use the address plug has a battery to maintain the memory (clock, address and temporary software) and IP settings. I'm no software boffin but the management system interfaces with the motronic, suspension and display. The logic gates might not like being without a source of power.
On my RT I lost nothing other than the clock setting when I replaced the battery. - twice in 6 years. Everything else was fine.