That's true, what Elina says. 3/5 or 4/4 doesn't matter at all. With 1/1 compared to 3/5 (or 4/4), there is actually a significant tax saving, provided the spouses' incomes are very different.
That it is explained correctly a thousand times here that the tax class has NOTHING to do with the actual tax burden, but is only to be understood as a "payment mode."
And then in post 67, someone comes along again who repeats the false theses that started the discussion ... it's simply maddening!