I grew out from a pixie and was at a chin-length bob when I found LHC. I carried on having trims but just spaced them further apart. It took me 3 years to go from chin-length bob to just past waist.
You will undoubtedly grow your hair longer, quicker if you don't have trims, but that was how I did it because my hair is quite thick with a slight wave and looks very untidy at shorter lengths unless it's professionally trimmed into some sort of style (and yes, I am vain).
My "3rd anniversary thread" has photos if you're interested.