As if the average modern day student is going to do this.
I did what OP did and it worked for me because instead of dozing off I was focused on keeping up with the lecturer. It worked for me personally.
More on topic, the standard vim-latex bindings are so incredible, for example "`a" (backtick + a) expands to "alpha", "`b" (backtick + b) expands to beta, then we also have "`/" (backtick + slash) which expands to "\frac{<++>}{<++>}" where "<++>" are called bullet points that you can jump to using <C-j>.
I too, was able to write LaTeX notes in class, it was awesome.