I wrote exactly the same thing (but in my own words) on another forum... ;-)Chassis dynamometers vary widely in measurement due to poor calibration and incorrectly applied correction factors. Any number you read should be taken with a very large grain of salt.
As a tool they are best used for back to back runs with tuning in between, the results should be equally inaccurate allowing you to see the before and after change. Comparing between dynos or results generated weeks apart, the variables are too big to conclude anything.
Any way the author isn't swaying the Fiesta ST is down on power, he is saying its better than Ford's rating.
He thinks the Focus ST is easier to drive fast which seems bizarre to me but he's Canadian, he might have a brain freeze or Hockey injury.