That's great. I like seeing new basses with fresh ideas coming out. Although I am a Fender player myself
... It's nice to see that people are pushing the envelope. What's crazy and unusual nowadays may become common in 20 years. Most electric basslines 30 years ago were played on 4 strings... wasn't much lower than the occasional dropped D note coming from the bass. These subcontras give range similar to an organ. Also, having all these strings allows a bassist to chord something high up, with an almost guitar-like sound, while a lead instrument solos or something. Not to mention the fact that it encourages a lot of creativity and gives much more options for a solo, whether or not you're playing with others. You won't often need tapping or double thumping in a song, but you learn it anyways... why? Because it's jsut another technique to say you can use if ever the time comes. With an 12 string, you've got everything at your disposal, basically, so what's to stop you? As long as you understand the bass and don't wank off on the Ab string during motown, more power to you.
EDIT: Actually, I take that back. If you can play motown on your Ab string and make it work, go for it man!

EDIT: Actually, I take that back. If you can play motown on your Ab string and make it work, go for it man!