Gel shoe inserts - Gel shoe inserts are not permitted, but shoes constructed with gel heels are allowed and must be removed and screened.

This is another one that often gets maligned by the public, and rightfully so because of how it's worded.

Specifically, they mean gel inserts for shoes. Like, it's a plastic bag in the shape of a foot that slides into your shoe, and if you squeeze it or fold it, you can literally see the gelatinous interior flowing around the bends and your fingers and stuff.

Common sense, incoming: The common Dr. Shoal's (sic)™ stuff at Wal-Mart doesn't count, given that it's soft, molded plastic, and not an actual "gel."