I know it sounds unbelieveable, but imagine catching a trout EVERY cast, frequently with only a 20' cast. Then imagine that many of these are 12" or less so there is a short fight. The really fun stuff came on longer casts with bigger fish, but the numbers are not my imagination. In one 20 minute period I caught and counted 22 trout (because sometimes it is too good to believe without proving it to yourself).
How? Well...
...by not using 7x tippet. I was using 6lb. Vanish flurocarbon which doesn't take babying, and
...by not casting too far (using a 6'3" 3wt short rod I wasn't going to cast a mile anyway) and
...by using a strip hook set which insured a lot more hook-ups and
...by paying attention to catching not having to replace many flies and
...by fishing on the Little Missouri in the first place.

Think of it this way. 40 fish an hour per fisherman for a 6 hour day would be 240 per or almost 500 in that one day. 30 per hour would be 350+ per day for two fishermen or 700 for two days. In fact, we were on the water for 8-9 hours a day so I'm discounting 3 hours for finding fish and eating a power bar and changing flies and potty breaks.