My friend dislikes Rubik's cubes, and he asked me how to frustrate amateur solvers by adversarially scrambling the cube. I expect that the answer depends highly on the particular solving algorithm.
Are there "human" algorithms for solving a Rubik's cube that are known to be very inefficient (compared to optimal) against particular "bad" configurations?
By "human", I mean the common algorithms that are taught in practice to amateurs or used by enthusiasts. There might be too much variety in common human techniques for this question to make sense, but even that would be good to know. (I'm looking for something more interesting than naive random walk, which is clearly almost always inefficient.)
And the relevant followup question:
Are there ways to find these bad configurations by applying random moves?
That is, is there an easy way to randomly generate hard cube instances for a particular human algorithm?
This is (somewhat) related to another question of mine about shortest paths to solution when randomly scrambling a Rubik's cube.