While this may have been true historically, my Catholic education specifically dealt with this subject by proclaiming that it was difficult, but not inpossible, for Salvation to occur outside the Catholic Church. And I should mention that I was exposed to this teaching just prior to the implementation of VaticanII as well, so I would expect that current teaching on this subject probably has an even more liberal interpretation than what I was raised with.
Either it's true or it's not true. It can't be true at one time, but be false at another time. I'm not surprised that your Catholic education was fudging the issue even before Vatican II. Fr. Feeney pointed out that this issue was the precursor to Vatican II.