[jakeru]

If the hard chromium plating on the strut shaft is worn, it could certainly cause a creaking noise. And after rotating the shaft a bit, since it would reposition the shaft to a different area which is rubbing against the seals and guides, it could certainly quiet down the noise. MacPherson struts, such as exist in our Boxster in both front and rear, place demanding, bending loads through the strut shafts. That said, the mileage your reporting is fairly low. I'd say the noise, being non-uniform from the strut shaft being turned, however, is evidence itself that your front struts are shot. The best way to test shocks would be cost-prohibitive for average case (as its labor intensive) - remove shocks/strut, place on shock dyno, compare result to manufacturer specs. This makes sense for expensive/custom racing type shocks, but for off-the-shelf shocks, it probably would make more sense given the the relatively low cost of the shocks to just replace them if they're exhibiting any bad symptoms or have high miles.