Yes, it does boot with the card installed as long as it is off, natch. I was delighted to see this too.

The downside is that if the card is on and you boot A/UX MacPartition, it gives you an unhelpful error message, and then proceeds to boot again from the same partition, in an endless loop. So I'll need to keep a rescue floppy with a Startup Disk control panel around if I forget to shut the card off when switching to A/UX. I imagine I'll have the same problem if I forget to have the card enabled when switching to 8.6.