How can I navigate by line breaks rather than by hard breaks when wrap is turned on, so that when I go down a line I actually go down the line I see rather than the source line in the file? This would be really useful when editing really long lines, such as what come out when I am editing TeX files.
You can change the default behaviour of
k adding the following lines to your
nmap <silent> j gj nmap <silent> k gk
See also vim tip 308