On the contrary. According to Robert Gibbs’ Whitehouse press briefing today:
“…now means yesterday – because when we said now we meant yesterday.”
In all seriousness, the question of a retrievable past has been a topic of debate ever since Dom Odo Casel proposed his liturgical theory that the actual sacrifice of Christ on the Cross was re-presented as an actual historical reality during the mass in order that the believer might be saved by joining in Christ’s sacrifice.
The Church condemned this theory, specifically Pope Pius XII in the encyclical Mediator Dei because it was felt that Casel’s theory pre-empted the doctrine of merit in which Christ’s sacrifice is sufficient to obtain salvation. Taken to its logical conclusion, Casel’s claim implied that it was actually necessary to sacrifice oneself along with Christ, by participating in a past historical event, made present through the Sacrament. The Church, on the other hand, claimed that the merit of this event was sufficient to save the believer without actually needing to return to that past event.
Essentially, because we have no need to return to the past event, it is irretrievable.
That being said, I am not sure that I completely agree with Pius XII’s evaluation. I am not prepared to make the same logical leap that because we do not need to return to the past event that it is therefore not made present during the Mass. Just because it is superfluous in one respect does not mean that is not necessary, appropriate, or fitting in another.