In other words, he's wrong, but he writes well.
No, not at all. Herman Hoeksema does write well. There are specific points where I do think he is wrong (though not always the same specific points that others on the thread mention). Because of his idiosyncrasy, I don't think it's possible to assume that when he explains the Catechism he is giving the original meaning accurately at all times. But his takes are invigorating, worth pondering, and yield something of value even if one quibbles over historical accuracy. In a long series of sermons on a document as complex as Heidelberg, such acknowledgements of areas of disagreement are likely both trivial and inevitable. In terms of theological writing, I think he likely represents the best the PRCA has to offer, and that best is very good indeed.
Seems to me that the former would cancel out the latter.
Only in a two-dimensional world. Sir Thomas Browne gets certain things wrong, of course, but there's a lot of value to be gleaned from what he says and from the way in which he says it.