Reintroduce the Spankings!

Kind of funny. A friend with a son who is now 12, advised me that I should "hang onto them while they are still babies". Her reasoning was that he is testing them, and has been challenging everything they say. My MOL recently said, "...now you have your hands full. When they get older, the head-games begin..." 
I'm wondering what in the hell they are all talking about - because my 3-year-old is already acting like she's 13! Time-outs have not been working... and for a while now. (Surprisingly, they still deter the near-2-year-old!) The back-talk, sass, and pure disobedience have been increasing in valor and frequency. 
We had attempted spanking them both initially - when discipline was due. However, that seemed to backfire. Every time they were angry with us, or each other, or didn't get their way - they would hit us/ each other. Not good. So we ceased and desisted - and went another route with the old "time-out". That worked incredibly well... and for quite some time. Sadly, it is time to move on... Before I throw something through a window!!
So - the other day, Myla had me stretched to my very limit. Blood boiling, and ears smoking, I grabbed her arm to position her for an all-out smack on the (diapered) arse! This took her aback (thank GOD, I'm running low on ideas with her ~ in her late-stage terrible-two's)... She cried out, "Mama... that HURTS!" I bellowed, "It's supposed to! It's called a SPANKING. And, it's what you're getting from now on every time you refuse to listen or talk back to mommy or daddy!!! By the way - this can be accomplished anywhere we go; The store, the credit union, grandma & grandpa's - ANYwhere!!! So I suggest you be GOOD and listen." 
Today, she decided to test me on that theory... I don't think she believed me. So I made sure this time. She didn't listen, and caused her sister great pain and agony. I spanked her. She cried again, and expressed her discontentment with this new ploy. In doing so - she decided to give me some sass... Stating that she was NOT going to listen to me... Hmmm. Well let's see about that then. SPANKING #2 ensued. A few tears (seemingly more out of frustration that she wasn't going to out-do me in the dual this time...) followed-by  - ah huh... more sass. So, Spanking number 3 ensued. More tears followed, when suddenly - she had on a halo. She was now "promising" mommy that she wouldn't do it again, and that she wanted to be a good girl. (Ahhhhh. The sweet smell of victory. Hmmm.... or is that a poopy-diaper?) PLEEEEEEEEEEASE Oh planets,keep this trend of successful discipline ongoing. Perhaps, if I'm a very good girl, Santa will grant me the ability to merely threaten the ominous "spanking" response in order to keep little sassy-pants in 'order' herself. 
Amen. (Wishing on stars, belief in Santa, and Prayer... Together, they have to get me somewhere!)

TIP! Sometimes, tough-love is necessary. If you had lived in my shoes for even just one day out of roughly the last 3 weeks, you'd agree. Maybe you agree anyway - as is probably the case for most parents who care about their children's well-being and their own level of sanity. In any case - I did what I had to do. When I told her "Mommy is in charge here, NOT you..." She responded by saying loudly and with vigor, "NO YOU'RE NOT! I AM in charge. I'm going to put you to BED!" [For the full effect, visualize arms folded and a "hmf!" to follow these words.] 
A QUOTE: "Loving discipline encourages a child to respect other people and live as a responsible, constructive citizen."  ~Dr. James Dobson
WHIDFML: Planned few errands for my "day off" this week, so as to allow adequate time for relaxation and rejuvenation. Ahhhh. Looking forward to that.