Thje guy that I bought the hive from showed me some larva and I saw it when I was with him. I even saw the queen in my small swarm before the combine because he saw it first and showed it to me. On my own I don't have a practiced eye and expecially when the bees are festooning and drawing wax. I am being so carefull trying to get the frames out and not break comb that everything else gets lost. On the young hives I even have a bit of a hard time seeing caped brood cause it is not in the bigg, round, cover the majority of the center of the frame but more like in the center of a quarter of the frame that was drawn first and seems to be a little darker then the honey caps.
Mostly for better or worse, since seeing a bit of capped brood in the bigg one and seeing the queen before the combine in the small one, I have not really looked at anything but rate of comb building, how strait it is and how much room they have.
I should have moved the outside frame in a bit but didn't like what the end of the comb at the end of the frame was doing and so didn't yet. On the ones that have the outside frames built out, I find it hard to get the first frame out with gloves on without tearing stuff up. I have the frames tight together but the honey bands on top are getting really wide anyway.
I expect to get more practice at some of this stuff.
I wouldn't combine swarms. I would let each one make a go of it because how they start is not necessarily how they end up.
I would have rather had four hives rather then three but keep thinking that there is a derth somewhere when they will quit drawing wax and that I need three mediums to winter with and I would rather have two hives survive and make a small split off them come spring than have 4 and only one live. I really don't know what to expect and would error on the side of caution rather then have to buy more bees.
I have the small swarm still in the trap but it is almost summer solstice and I don't know what can and can not be done and as you said you can't see them so I just have to do my best guess and hope it works.
I don't even know the simple things like if I only had one medium built out would they have a better chance in winter being moved to 2 stack 5 frame nuc or left in what they put together or thrown in with something bigger and then taken out in spring.
I just keep looking listening and expermenting and trying to not repeat mistake after I figure out it was a mistake.