He would have had a mess to deal with us but Derby had a squad to build from and he joined them with a pre-season to work from as well. Whereas with us it was in an instant pressure situation without time to develop the team.
He has done an excellent job at Derby but that doesn't automatically mean he would have been great with us because of the different circumstances.
I wouldn't argue more or less tough, rather it is different. With us, he would have come in right in a relegation battle with no transfer window to sign players whilst at Derby, he had a pre-season to build a style he wanted and to sign players to fit that.