That 'convert everything to grayscale first' tip from my print shop guy... turned out half right?
My guy at the local shop in Toledo told me last spring to always flatten layers and convert to grayscale before doing any CMYK mockups. Said it would 'expose the contrast lies' my screen was telling me. So I tried it on this poster with a deep purple background and orange text. Sure enough, in grayscale the text just vanished, which was a real problem. But I took his advice too literally, set my whole file to grayscale mode, and then when I switched back to CMYK the purple got all muddy and banded. Took me 2 hours to rebuild the gradient. So his core idea helped me spot the issue, but the actual workflow he gave me was garbage for final files. Is that a common thing, where old school tricks are good for checking but not for building? Or did I just do his method wrong? Has anyone else had a 'wisdom' that worked in theory but wrecked their actual file?