pySQLite Insert speed

[mdboldin at gmail.com]

I hav read on this forum that SQL coding (A) below is preferred over
(B), but I find (B) is much faster (20-40% faster)

(A)

    sqla= 'INSERT INTO DTABLE1 VALUES (%d, %d, %d, %f)'  %  values
    curs.execute(sqla)

(B)
     pf= '?, ?, ?, ?'
    sqlxb= 'INSERT INTO DTABLE2 VALUES ( %s ) ' % pf
    curs.execute( sqlxb, values )

Any intution on why (A) is slower?