In an accident analysis thread, a participant made a point that permanent markings and not temporary markings should be used to identify scuba tank contents.

I believe this practice got kick started with the WKPP project and it proved to be a safe way (combined with operational procedures) to execute complex dives involving various travel, bottom and deco mixes.

Many people seem to have adopted this practice only partially. While diving at Ginnie and Peacock mostly in the last couple of years, I saw tanks with all sorts of MOD that made me believe they were not dedicated tanks. At Ginnie, in my last two trips, I noticed stages with MODs from 70 feet to 130. I rented myself a 100 foot tank that was not filled with EAN 34.

My practice when cave diving (single gas + o2) is to analyze all main, stage and deco bottles when the gear is setted up (on stages, I analyze when ready to install my regulator). On Caribbean dive trips, I analyze, mark and log analyses as per recreational standards.

Am I alone feeling that permanently marked tanks are not dedicated in real life?