"highland provides a lot of of the functions from underscore.js"
"A lot of the functions" (versus "all of the functions") sounds like a one-way ticket to readability hell, since it means that an inattentive reader may assume the functions ARE from Underscore.
To me the benefit of a convenient shorthand outweighs this, someone would figure it out really quick, seems like a non-issue. A few different libs use $ and the world doesn't end.
"A lot of the functions" (versus "all of the functions") sounds like a one-way ticket to readability hell, since it means that an inattentive reader may assume the functions ARE from Underscore.