Why these stories? Because it's August and no one wants to think. Because the campaign is too long and reporters have to write about something.
Nonetheless, at a time in our history when presidential races are won and lost by a few thousand votes, candidates for first spouse do matter at the margin. Who can deny that a factor in Hillary Clinton's bid for the White House is voters' hopes and fears about how husband Bill will behave and misbehave as first spouse?
Leaving aside the special case of Bill Clinton, Peggy summarizes her advice for potential first ladies as follows:
First ladies were once more or less average, and were expected to be. Now they are accomplished, worldly, and expected to be. Candidates for the first lady's job have to find a balance. It's delicate. Strong is good, aggressive not. A person who cares, yes; a person who pushes an agenda, no.