Users can change columns widths of the grid with their mouse. But there is no api methods to arbitrarily set column width in js. We implemented it using manipulating the DOM and a number of "hacks" to force the grid to recalculate it. But such implementation is complicated, quirky, inefficient and unstable.
It would be very useful if such methods were implemented. Reordering, hiding and locking already has its methods, only resizing doesn't. We use it to save and load user's settings.