[bacon_waffle]

A friend who makes things for a living, once went on a wonderful rant about how "just", especially after "you" (can't you just...), must be one of the rudest words in English.

The gist was that just, used like this, often implies that the speaker not only knows how to accomplish the solution, but can't be bothered to do it themselves. At the same time, they don't see the difficulties in the problem, so won't value a good solution if one is made.

I thought it was a keen observation, and have since tried to think again before using "just".