Absolutely true, and too many people have become over-reliant on intra-cell interpolations by fancy software with pretty pictures. Looking at CAPE charts and the 850mb chart helps...but a little meteorology knowledge, experience, situational awareness, and the resulting feel for the weather helps more.yes, exactly.
A small complication is that the gribs particularly (but also the 'human' met products, especially offshore) systematically underrepresent these 'small hot zones'. So you as the user need to have enough knowledge/experience to know when they will likely be there based on the system that is shown. This has gotten better over time as grib cell sizes have decreased but is still an area where human judgement and art is quite valuable.