Does the sifting of flour have any effect on how bread turns out?
If you're using wholemeal it will remove all of the bran and coarse bits - but pesonally I like those. If you're living in mediaeval conditions, it will sift out mealy bugs and weevils. If you are buying flour from a reputable shop, all of those bits have been sifted out. So save yourself the bother and just bake with it!
I don't think andrew_I's comment have much validity, except if the flour is old which I don't buy.
I normally buy 25kg bags with milling date and batch number on its side no older than three months after miiling datei s my cut off point.
On the other hand sifting of flour aereates the flour before machine mixing and it is good practice to do so while the mixing is on.