Collect yeast from Tap-a-draft bottle?

I've noticed there's a decent amount of yeast left in the bottom of my TAD bottles when I'm done with them. I haven't collected any to see how much it is, but it looks like it could be enough to make a starter from.

Would it be a good/bad idea to collect this yeast? Any potential problems from having it go through bottle conditioning and what not rather than collecting/washing directly from fermenter (i.e., yeast digesting dextrose during bottle conditioning making them less adept at digesting wort?)?

It should work but it's not ideal because, unless you're kraeusening with fresh yeast, you're selecting the least flocculent cells.

Ahh, good point, I hadn't thought of that, thanks for the reply.