Yes, this is true, as I mentioned in a post somewhere before. The trailer company in those days of actual celluloid got a complete b&w copy of the color workprint well before the picture was "locked." This included scenes which eventually were trimmed or edited out of the picture, so the trailer had stuff in it which could be called confusing (but not necessarily meant to be misleading -- the trailer people simply cut the most exciting trailer they could from the footage available).Harley wrote: They probably hadn't finished editing when the trailer was made so a lot of small bits here and there are probably in there that didn't make the final cut.
As to the 90 minute running length of the movie, it just turned out that way.
dh