Even if the currents were at a leisurely walk of 3 Knots x 24 hours in a day (currents never sleep) = Debris Field 72 miles from ditching / impact in just one day
It is now going on 15 days since MH370 went missing
15 days x 72 miles = 1080 NM from ditching / impact
Now going back to basic pilot trainer class if you are one degree off course in 60 miles you will be one mile off course.
1080 / 60 = 18 miles plus or minus the debris field could be located with just one degree change in the ocean currents vs. those who plot the currents.
All of these numbers could be multiplied by two or three with all the verbals in the Southern Indian Ocean.