Uncommon
A nice post, OK I will back off.
Sending a 172b with 40 degrees down around at 300 feet for 'economic reasons' SHEER BLOODY LUNACY if you ask me.
'Turn right overwater' except both right and left from there are overwater, following an unusual and unexpected 'command'.
To quote the pilot "i am OK but the Dash-8 passengers are still in therapy'
Were I to apportion blame it would go
1. The econorats for the silly 'procedure' you quote.
2. ATC for doing it.
3. The pilot for not saying, 'negative, continued approach at this point REQUIRED'
after all, who was only holding the tail.