the bane of rolling pins is soaking in water (which will raise the grain on the wood and if left long enough, can even split it) & washing it too often with soapy water ( which will remove the natural wood oils and dry out the pin).
if you dust your dough properly, nothing should ever stick to the pin. if you have an occasional run-in with a glob of butter or something it's ok to wash it, as long as you don't make a practice of washing it every time. dry it thoroughly and it'll be fine. otherwise, just brush off the flour with your hands or a dry cloth.
the same goes for an old-fashioned sifter. tap off most of the flour by hand and dust off the rest (if you want) with a dry cloth. if you wash these, the flour in the cracks and hard-to-reach places turn into a paste, dry, crack into hard little nuggets which eventually find their way into your cakes and muffins. washing these also leads to rusting. if you do need to wash one, drying it off in a slow oven is best.
as for soaking pins in mineral oil, it's not only unnecessary, but as an amatuer woodworker, i know that too much oil can cause grain and warping problems in wood. with rolling pins, drying out is not a problem if you usually just dust them off. cutting boards, however, get washed frequently and will benefit if you rub in a little mineral oil once a year or so.