Which is it Re Miers?

If I remember correctly, conservatives (correctly) argued that it was inappropriate to ask John Roberts about his views on particular cases/issues that were likely to come before him as a Justice of the Supreme Court. We weren't supposed to know what his specific views were, based on the "Ginsburg Rule," i.e., Ruth Bader Ginsburg's similar refusal in 1993 to tell the Senate what her views on Roe, etc. were. Now, if I understand what everyone is saying, Harriet Miers is not to be trusted as a nominee because we don't know how she will rule on particular issues. So which is it?