What do you mean, Eliot?

Saussure’s argument about signs being not only connections between signifier/signified but also value comparisons between various signs implies a problem with New Criticism, doesn’t it?  Don’t we have to look outside the poem/text to look at how its words interact with other words (indeed, otherwise it would be unintelligible), and perhaps by extension also look at how the text as a whole is interacting with other texts?  Would the New Critics disagree with this?  They want the text to speak for itself, and not rely on author or context… but for them, are texts isolated?  If so, how can they have any meaning, according to Saussure’s model?