I believe there is a marvelous, wonderful, awe-inspiring power inherent in the idea of working as a savior on Mount Zion - of turning our hearts to our ancestors in a manifestation of love and humility - that I haven't found in any other construct outside of vicarious temple ordinances. In that regard, I believe we perform vicarious temple ordinances for the symbolism as it relates to us - and for what it does for us in a very important way - every bit as much as for the literal effect it might have on the dead. Vicarious ordinances really are an important part of the living Gospel for me, but that's mostly because I accept the symbolism as extremely powerful and paradigm-altering. I would love it for that reason alone, even if I didn't believe it had any literal impact on those for whom the ordinances are preformed.
Having said that, I believe if we miss the symbolism and what it can do for us by limiting it solely to its impact on the dead, it's just another dead work. (pun not intended when I typed those words, but . . .)