I found George A. Smith tells the story of Marsh that was repeated so much in 1855.

Could George A. Smith’s story be true. Yes. Why, because he was in the quorum of twelve apostles with Marsh.

Do we know the story is accurately told. Of course not. But pretty much no historical story is 100% accurate.

Wik calls the story unsubstantiated, but that does not mean that it is false.

I have sometimes observed teachers who gave the designated chapter no more than a casual mention and then presented a lesson and invited discussion on other materials of the teacher’s choice. That is not acceptable. A gospel teacher is not called to choose the subject of the lesson but to teach and discuss what has been specified. Gospel teachers should also be scrupulous to avoid hobby topics, personal speculations, and controversial subjects. The Lord’s revelations and the directions of His servants are clear on this point. We should all be mindful of President Spencer W. Kimball’s great instruction that a gospel teacher is a “guest”:

“He has been given an authoritative position and a stamp of approval is placed upon him, and those whom he teaches are justified in assuming that, having been chosen and sustained in the proper order, he represents the Church and the things which he teaches are approved by the Church. No matter how brilliant he may be and how many new truths he may think he has found, he has no right to go beyond the program of the Church.”

I generally don’t speak up if the issue is minor, but I have spoken up from time to time. I can’t remember the last time I did however.

In our WOW lesson, we didn’t go into detail about what is and isn’t against the WOW, so I avoided the issue you experienced.

But your original question. Unless really detrimental (and that is a subjective decision), or if I can’t present it in a light hearted manner, or my judgment of the testimonial strength of the person I would be disagreeing with, or the flow of the class would seriously be damaged; I would just keep quiet. My last disagreement was a lesson on the WoW when the teacher stated caffiene was breaking it. But on the same lesson I didn’t mention anything about its status change to requirement (and thus its nonenforcement prior to that change), the non WoW practices pf prior church leaders, or the funny stories within the Prince McKay bio. Because while I find them interesting and/or funny, they would have disrupted the teacher’s lesson and not particularly helpful.

I’m not sure I would like a chronological format; that would seem to promote more of a church history lesson, from which I try to shy away.

When I taught GD I never used the manual once. I just started in versus one of the book we were studying and then just progressed through as the year went on. With the D&C I just taught them in chronological order. Not everyone liked the loose format but I sure did; and as the teacher my vote counted more.