If you have a dummy board in your hive there's no real need to put the frames you are inspecting anywhere .. take the dummy board out - shake what few bees there are on it off - lean it up somewhere convenient ... you can then move the next frame along, lift out, check and replace.
I don't like frames outside of the hive for any length of time and I certainly don't like frames covered in bees on a frame hanger outside the hive - recipe for a disaster. Keep frames above the hive and you know where the queen is going to drop if she falls off and with a dummy board you are not going to roll bees as you take it out ... OK - the end frames may be stores but squashing bees as you prise out the first one is going to upset them and I have, on occasions, found a queen on a frame of stores.
When you get to the end of the inspection all the frames are together at one end of the box .. use your hive tool to push them all back in one movement (that way you don't squash any bees) and replace the dummy at the end ... job done.
I'm sure as an experienced keeper you know most of this but it's the Beginners section and some newbies might not appreciate the benefits of a dummy board.
Unless you have castellations rather than runners in your brood box ... I know there's a few eccentrics who use castellations in their brood boxes but I think their place is in the supers - you could still use a dummy board but it rather defeats their use with castellations.