YES it IS possible to dodge a blue leader shell. Just make you sure you have a mushroom and then fire it right as the blue shell hovers over you. For help with timing watch this how to vid:
Want to master Microsoft Excel and take your work-from-home job prospects to the next level? Jump-start your career with our Premium A-to-Z Microsoft Excel Training Bundle from the new Gadget Hacks Shop and get lifetime access to more than 40 hours of Basic to Advanced instruction on functions, formula, tools, and more.