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DC sweep is basically a repeated DC operating point and so the issues relating to that mode also apply to DC sweep. However, if you are sweeping a voltage or current source, then an altogether better way of dealing with DC sweep problems is to simulate the DC sweep using transient analysis with a slow ramp.
Using transient analysis to perform DC sweep also resolves problems that can occur with circuits that have regions where there is more than one stable state e.g. bistables or schmitt triggers. Consider sweeping the input voltage of a schmitt trigger circuit. When the input voltage is between the lower and upper thresholds, the circuit has two stable states and the DC algorithm could find either of them. As each step in a DC analysis is initialised with the previous step, it will usually find the correct solution but this is not guaranteed. This means that the output could change state even though the input has not passed either threshold. This problem doesn't occur in transient analysis as in this mode the circuit is running as it would in real life.
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