But seriously folks,  how do you decide when to produce a Gantt Chart and when the time and effort is just not worth it for the job at hand.  As with most things in life , it is all relative.
How many times have you produced a full blown Gantt Chart for a small job and decided that producing the chart has proven to be a bigger effort than the job itself.
How many times have you run what you though was a small job without a Gantt Chart and wished that you had gone to the effort of producing one.

I guess that there is no easy answer and  it becomes a value judgement decision. A lot depends on the job and the individual person running the job.
I tend to consider the complexity more than the value and also if other people are involved.
The value of the project can be quite irrelevant as (for example) installing an expensive item where the majority of the cost is in the item itself might only involve a small number of activities which can be quite easily controlled.  
Conversely a complicated install needing critical timing with a production operation may have great complexity and involve many others but be of low capital value, tho' with an expensive impact if it doesn't come together or work.

I don't think that anyone would argue against a Gantt Chart for complex Projects.  It fact I think that most people would see them as absolutely essential.  But how do you gauge when the Chart might become a bigger task than the job itself.
And that ….. as Shakespeare said all those years ago, "Is the Question"