Well, doing the math, Howard could techinically be acquired through a S&T with the Lakers, but only if included in the deal with Brooklyn. But yes, this is a pipe-dream.
This trade would work under the CBA (provided the tax apron goes up a few million for 2013/14).
Boston
Howard-$20,153,178
Humphries-$12,000,000
Wallace-$10,105,855
Lakers
Bass-$6,450,000
Crawford-$2,162,419
Sullinger-$1.365,720
Teletovic-$3,229,050
Brooks-$1,210,080
Draft right's to Olynk
2014 1st-Bos
2014 1st-BKN
2016 1st-BKN
2018 1st-BKN
Brooklyn
Pierce-$15,333,334
Garnett-$12,433,735
Terry-$5,225,000
A subsequent deal could then be made with Atlanta in which Smith was acquired through a S&T for Humphries, Bradley & the better of our 2015 1st or the Clippers 2015 1st.