BUt the wide ones have the same problem, they leave the outermost layers of filler moist while the innermost are dry. IME, anyway. And in any case, as I've said before, we have to prioratize, we can't add every conceivable option at the same time, and fat batts and cartos are lower on the list than other ideas. An extra long carto compatible with MF batts is more doable right now. IF it works to my satisfaction.