"As a conclusion, it is reasonable to assume that the expansion of the universe affects all scales, but the magnitude of the effect is essentially negligible for local systems, even at the scale of galactic clusters. So I suspect one of you is wrong. :-)" 
Indeed. They textually claim that "the magnitude of the effect is essentially negligible for local systems," whereas I do the actual Inflationary Theory math to show that the effect over 17 Billion years would be more than 123 AU between the Earth and Sun per their own theory.
Since the distance is 1 AU instead of 123, they must be wrong per the math.
Math isn't debatable. Calculations may be wrong, theories may be wrong, formulas may be wrong...but the math tells the tale.
And Inflationary Theory's math is the Pinnochio of Science.
Since the distance is 1 AU instead of 123, they must be wrong per the math.Well then, I have two questions: At which equation exactly did they go off the rails, and are you going to email them to inform them of their blunder? I'm sure if you approach them politely they'd appreciate the correction.
But wait.
Let's look at your math again.
I presume that you're using 17 billion years for the age of the universe?
Do the same math against using perhaps 4 billion years, as the age of the earth (since obviously the earth wouldn't have been caught up in expansion that happened before the Earth formed).
What result?