DOC I didn't mean soft-O by "tilde notation"

Author: larsmans

doc/developers/index.rst

@@ -225,9 +225,8 @@ Basically, to elaborate on the above, it is best to always
 start with a small paragraph with a hand-waiving explanation of what the
 method does to the data. Then, it is very helpful
 to point out why the feature is useful and when it should be used -
-the latter also including expected *big-O*
-( :math:`O\left(g\left(n\right)\right)` )and
-*soft-O* ( :math:`\tilde{O}\left(g\left(n\right)\right)` )
+the latter also including "big O"
+(:math:`O\left(g\left(n\right)\right)`)
 complexities of the algorithm, as opposed to just *rules of thumb*,
 as the latter can be very machine-dependent.
 If those complexities are not available, then rules of thumb