Looking on his
Selections page, you will find his quotes on
Limbo. If one takes the time to examine his views on
Limbo and its status as doctrinal teaching, one will find a statement wherein he dismisses the validity of Canon 1261 (which is part of the law, not a mere footnote, as is shown
here).
As for “the heresies of the day”, if you can give me something specific I might be able to comment on that - as far as I am aware, the Church rebukes those in manifest schism, as She did with former archbishop Lefebvre. However, if you consider, for example, receiving communion in the hand instead of on the tongue a heresy, or something to that effect, then we really have nothing further to discuss.