I got the Wrox.Beginning.JavaScript.3rd.Edition and wanted to start learning it from scratch, then my boss came along and said that why bother, learn jQuery. Can I understand jQ
It is entirely possible to learn jQuery without learning every bit of javascript first. However, to be productive and and extend the functionality of plugins etc you will need to know javascript.
I would suggest that you do a bit of both. Continue learning Javascript but when you want to implement functionality make use of the jQuery library.