If someone believes a fish will grow to "fit" a tank, then they are saying that stunted grow is healthy.
The bottom line, IMO
, is that recommended tank sizes are great guidelines for any fish, not just Tangs. You rarely see people following those guidelines posting about their fish having problems (assuming of course that they are maintaining water properly and considering compatibility issues with tank mates as well). Tangs need lots of room or they stress. Stress effects them more than most other fish. naturally thin slime coats plus lowered immune system equals health issues.