When we read a Victorian-era translation into English of Garcilaso, we have a third element to think about that has not much to do with Garcilaso or with ourselves. In other words, we could read Garcilaso directly, or even with the help of a more recent translation if we don't know Spanish well, but our interest in Garcilaso is independent of whatever interest we have in Victorian era poetry. So all the Victorian detritus is precisely what we aren't interested in, because it is irrelevant. We want a 21st-century understanding not mediated by some distracting 19th-century understanding of the 16th century.
And if we are judging it by our own standards, we might not like it; it might not be our own taste. And maybe Victorian translators have different ideas about literalness and so we can take issue with their accuracy.
Yet we are also entitled to be interested in 19th century translation practices in their own right, and in the history of the reception of Garcilaso. Now are question is not: how good was Wiffen as a translator of Garcilaso, but rather, what were contemporary ideas about translation? So questions of both taste and fidelity take a back seat.
Yet it precisely in these two areas, taste and fidelity, that we can make judgments about what Victorian translation ideals were about. Those are the things we notice, especially when they depart from our own preconceptions. Insofar as they are in accordance with our own ideals, translations become less visible.
The wonderful moments come when a translation is really awful or really wonderful. We can have a Chapman's Homer Keatsian epiphany, or feel such a gap in the translation that an abyss opens up for us: how did he get it so wrong?
Translation is hermeneutics, but it is also aesthetics.