I agree with Gerard ... and also with Ed.
As Ed says, once a stake gets past a certain size, time becomes a factor.
And although Gerard did not say it in this way, time impacts the types of tests you put on.
If you know you have a 100 plus dog field, time management becomes critical. If you run a wide open triple - you can plan on 8 minutes per dog - if you are cooking with gas ... and everything is perfect in the field.
Take Wichita Falls as an example
So 120 dogs x 8 minutes = 960 minutes / 60 = 16.0 hours
Sunrise is 6:30 am
Sunset is 6:30 pm
Assume you are really on top of your game and run your first competing dog at 8 am and continuing running dogs at an eight minute per dog clip until 6 pm. You have still 10 hours and still have 6 hours of dogs to run.
By necessity, you have split the field. If you are lucky, the wind will hold and not shift on you and give away all of your birds.
So Saturday you begin at 8 am, this means land marks finish at 2 pm.
Assume setup of land blind and running of test dog takes one hour. You are now at 3 pm.
Assume you lose 50% of your field on land marks. You have 60 dogs still in contention.
Assume land blind takes 4 minutes per dog. 60 dogs x 4 minutes/dog = 240 minutes
240 minutes divided by 60 minutes/hour = 4 hours
You finish land blind at 7 pm.
Assume you lose 50% of your dogs on land blind. You have 30 dogs in contention.
On Sunday, you start at 8 am.
Water blind takes 7 minutes per dog. 30 dogs x 7 minutes per dog = 210 minutes
210 minutes divided by 60 minutes/hour = 3.5 hours
You finish water blind at 11:30 am.
It takes one hour to set up water marks.
Assume you lose 50% of your dogs. You have 15 dogs in contention.
You start water marks at 12:30 pm
Water marks take 15 minutes per dog. 15 dogs x 15 minutes per dog = 225 minutes
225 minutes divided by 60 minutes = 3.75 hours
You are done at 4:15 pm.
This scenario assumes everything runs like clockwork.
If the trains run on time and everything is ready to run when it should and there is no waiting on dogs.
If the tests work as intended and get answers.
If the dogs run at projected time or less.
Then you get done with the Open in three days, running 10 hours per day, with an hour and forty five minutes to spare.
There is no margin for error.
Miss anywhere along the line and you are running dogs on Monday ... or pencil whipping the field like a mad man.