Most comment on these forums is quite negative,
I do hope you mean only specificlly re brood and a half!
It has been used for generations, even before the standard for the UK beehive came into use, so was a popular choice.
Don't know whether they tended to condense the hive to a single brood and overwinter on a brood and a super of honey or just filled the boxes.
For some reason (probably down to the normal deep brood being big enough for most colonies/strains (of the day), most of the time (when the standard was set up) and the distinct apparent dislike of the extra-deep frames, the 14 x 12 was never popular.
A 14 x 12 is now more popular than a brood and a half, I would say, so people have been enlightened over the last decade. It is nearly equivalent to your present format, but has several advantages. Double brood also is favoured over brood and a half, but is considerably larger than the 14 x 12, and has the simple advantages of weight of a single box, frames that can be used in the top or bottom brood, frames that are easier to get drawn out (and straight) and are often over-wintered on the one box.
That rather leaves the brood and a half in the middle of nowhere. In all honesty I would have made sure my queen was in the deep box and inserted a Q/E between the boxes and reverted to single brood in three weeks or 24 days (drones), if she does not need to fill two boxes (peak lay-rate is possibly passed already for this season).
Don't beat yourself up at getting in the mess with the queen laying upstairs - it happens to all of us at some time. Just don't commit yourself to everlasting brood and a half, is my advice.
RAB