I'm not a Catholic, but I have to disagree with the premise of the question. As Svidgen points out God is omnipresent - or as I prefer to think it God is beyond time. He transcends time. If one is drawn to where God is, one is drawn out of time altogether.
That the communion of saints is tied to the Eucharist is attested to in the "Dictionary of the Church in America" It says:
some Christians believe that their “communion” or fellowship is most tangibly expressed through the celebration of the Lord’s Supper, and the phrase “communion of saints” can also be translated “communion of holy things” to describe the church as a sacramental community.
Thus, any theory of communion that holds the worshipper and the celebrant are in the presence of God via this communion of the saints can thus claim this "time travel." This would adhere to Lutherans, Episcopalians, and any non strictly-memorialist understanding of the Eucharist. In other words, Baptists stay where they are, but everyone else joins the "communion of saints" which is beyond time.
This is corroborated by the "New Dictionary of Theology" which states (emphasis mine):
In the Middle Ages it was believed that a Christian could enjoy the communion of saints only by remaining a member of the Roman or of one of the Eastern Churches. This view is still the official position of these churches, but it was rejected by the Protestant Reformers, who followed the NT and defined a saint as any true believer in Christ. It followed from this that not all members of the visible church were saints, and although mainline Protestantism accommodated itself to this discrepancy, there have always been sectarian groups who have seceded from the major denominations in the hope of founding a pure church, consisting exclusively of ‘saints’.
At the present time, the doctrine of the communion of saints is generally interpreted according to the dimensions of both time and space. In time, it is taken to mean the fellowship of Christians in every age, past, present and future. In practical terms, this means that the church today has a duty to preserve the faith which it has inherited from the past, and to transmit it unimpaired to future generations. Roman Catholic Christians also maintain that it has a direct bearing on the church triumphant in heaven, and use the doctrine as a justification for praying to the dead, especially to the officially canonized ‘saints’. Protestants vigorously reject this interpretation, because prayer may properly be offered only to God, because Jesus Christ, not the saints, is the one mediator between God and man (1 Tim. 2:5) and because the church triumphant has entered into eternal rest.
No less a cholar than Karl Barth picks up on this:
We should note that Fasholé—Luke’s interpretation of sanctorum comes from Karl Barth’s suggestion that it is intentionally ambiguous, being both masculine plural and neuter plural.22 He follows Barth while fully recognizing the problem of interpretation of the expression sanctorum communionem. F. Prat, for instance, emphatically states that the word sanctorum is masculine and not neuter.23 In that case, the communion is the solidarity of all the members of Christ’s body, both the dead and the living. ... At the Eucharist Christians join with the whole company of heaven, the faithful departed, the angels and archangels, to praise and glorify God. … It is at this service that we can and do live with our dead in a way which is profoundly true to man’s nature
(con|tran)substantiationrather thantime travel. – Caleb♦ Mar 20 at 13:30