Just who is making this claim?
And in what condition is the machine when it's achieving this result?
The thing is, as you asked the question, it's impossible to answer. Let's just go back to the basic rule that RIP's convert pixels into dots using information given to them by profiles. So a printer profile tells every printer that ever made any dot how to create that dot.
I guarantee you, I can make one printer waste a whole lot of ink, or be very miserly with ink, purely by making a profile to do so.
And odds are you're going to have a great deal of trouble selling the output from the most miserly profile I can make. The first color to go when cutting too far back on ink is always red. And red is what most clients insist on.
I'd also point out that the reason many printers have high ink costs is that they throw a lot of ink into the dumpster in the form of patches printed chasing color, or jobs re-run for bad color.
The best way to make money in large format printing is to print the best possible job your printer can print, first sheet, every time. That's the one true way to lower your material costs.
Mike Adams
Correct Color