Nothing better than a picture. I have taken the liberty to add to your plot.I believe my plot is about right. Mr. Groves sees the Titanic somewhere around SE and some 20 minutes later she stops around SSE. What is wrong with this? Could you please explain?
I have added the the path of a 22.5 knots vessel on a course of 265 True first seen at 11-40 pm from the bridge of Californian and how Californian would need to have been heading at 11-40pm if she was swinging right at the rate of 1 degree/minute. I have shown that same 22.5 knots vessel stopped, slightly abaft the Stbd. beam at 12-10 am when Stone relieved Groves. I quote:
On going up to the bridge I was stopped by yourself at the wheelhouse door, and you gave me verbal orders for the Watch. You showed me a steamer a little abaft of our Star-beam and informed me she was stopped.
Now do you understand?