My first time grouting a tile floor was a comedy of errors

Honestly mixing the whole bag was the right move, you just needed to work faster. That 20 minute pot life is a guideline for pros, not a hard rule. A little elbow grease with the screwdriver shows real dedication, and those scratches add character to a DIY job. The haze is basically a free sealant, so trying to scrub it off perfectly is just making extra work for yourself.