My Rocna anchor is fantastic, but it always seems to come up into the stem head roller the wrong way round. This looks like the effect of the water flow over it causing it to turn over. Does anybody else recognize this problem?

Hi John,
I am glad you have had such good luck with your Rocna. It, like many of the new gen anchors, are amazing at initial setting when they are clean.
The following should be read as written from someone who believes a ground tackle system, in its proper design and execution, sometimes (perhaps often) has you and your crew’s life residing in its effectiveness. There are those that say that they rarely spend the night at anchor, usually use it as a lunch hook or for fishing: to them, I would say that it is also there for emergencies, unexpected squalls and engine breakdowns, where a good system proves itself invaluable. Those of us who cruise know how important it is at least a few times each season.
I would want you (or anyone with a swivel) to consider ditching the swivel for the following reasons:
The ground tackle system is to keep your boat and crew safe and nothing in that system should compromise that goal. I believe swivels do so compromise:
1.   Attached as advertised (looking at the Ultra’s web site the installation is straight onto the anchor) introduces the possibility of the anchor getting jammed and side loads prying the jaws apart. (Google anchor swivel failures for examples.) Adding a bit of connecting chain, as Daria suggests, mitigates that issue while introducing even more shackle connections (every connection is a potential vulnerability) and the likelihood that the one favored reason for buying a swivel (clean retrieval onto a roller) would no longer work so effectively.
2.   The Ultra (and most highly advertised and hyped swivels) is made of stainless steel and ss (in my judgment) has no place in a ground tackle system that, by definition, is in and out of salt water. It is potentially too brittle and prone to crevice corrosion and there are alternatives, all better, to ss shackles, anchors, chain etc. that one sees wherever there are boats.
3.   With the possible exception of anchoring for long periods where the boat circles its anchor repeatedly CW or CCW (and I have lived this scenario a couple of times without a swivel), a swivel does not contribute to the effectiveness of one’s ground tackle. Chain twist is always relieved by an adequate snubber.
4.   The advertised strength exceeding chain does not specify whether proof coil or high tensile. Among cruisers, HT is becoming more common. I would be in its strength if the anchor end was held rigid and the pull at right angles.
5.   An anchor that comes up backward is annoying and can entail a bit of fussing, but introducing a vulnerability into one’s ground tackle system in order not to be occasionally annoyed is (again my opinion) in no way justified.
My best, Dick Stevenson, s/v Alchemy