Taking a clone while in flower is what's known as "monster cropping" and indeed it does give tons of extra shoots compared to a clone taken in veg. Some might argue it's not worth it because of the extra time it takes to reveg it VS just taking the clone during veg to begin with. I like the outcome of what monster cropping does so I'd say go for it.
I think not misting the clones at all for the first few days could be bad for them because their only way to feed is going to be through the leaves. I'm sure either can work, just my opinion on that one.
I've tried misting + doming, misting + no dome, no mist + dome, and no mist + no dome.
What worked best for me was to mist 4 times a day and not dome at all. Second best was to mist 4 times a day plus have a dome WITH holes in it so it could still get fresh air. The other methods I ended up with mold and or they just never rooted and died. But they all definitely liked having a heating pad under them on low and it sped up the process considerably.
Last thing is I've heard of tons of members here simply taking their cutting and leaving them in a glass of plain old water to root with great success. I haven't tried this method yet.
Peace. =)