Bart,
The Lehmann dough formulation you posted was the original Lehmann dough formulation that I posted in the first message at the Lehmann thread at
http://www.pizzamaking.com/forum/index.php/topic,576.0.html. That was long before I really knew what I was doing and when I was just starting to learn about baker’s percents and thickness factors and how to use them. I also didn’t have the benefit of the Lehmann dough calculating tool to help me with the ingredient quantities. You will also note that I made an error in the amount of IDY used in the original recipe, even though I got good results notwithstanding the error. Today, I would be more inclined to use the following Lehmann dough formulation, for which I used the Lehmann dough calculating tool to calculate the ingredients needed to make a 16” pizza:
Flour (100%): Water (63%): IDY (0.25%): Salt (1.75%): Oil (1%): Total (166%):
 343.38 g  12.11 oz  0.76 lbs 216.33 g  7.63 oz  0.48 lbs 0.86 g  0.03 oz  0 lbs  0.28 tsp  0.09 tbsp 6.01 g  0.21 oz  0.01 lbs  1.08 tsp  0.36 tbsp 3.43 g  0.12 oz  0.01 lbs  0.76 tsp  0.25 tbsp 570.01 g  20.11 oz  1.26 lbs  TF = 0.1

As mentioned above, this formulation is intended for a 16” pizza. However, one can make two roughly 12” pizzas with the same amount of dough. As you noted, when you plan to make more than one pizza from a given amount of dough, it is usually a good idea to divide and shape the dough into nice round dough balls before refrigerating the dough.
Since you asked about how to alter the dough formulation you used to make a 14” pizza instead of a 16” pizza, I calculated the baker’s percents for the original Lehmann dough formulation and, using the Lehmann dough calculating tool and a thickness factor of 0.10, came up with the following for the 14" size:
Flour (100%): Water (65.2542%): IDY (1.69491%): Salt (1.69491%): Oil (1.01694%): Total (169.66096%):
 257.23 g  9.07 oz  0.57 lbs 167.85 g  5.92 oz  0.37 lbs 4.36 g  0.15 oz  0.01 lbs  1.45 tsp  0.48 tbsp 4.36 g  0.15 oz  0.01 lbs  0.78 tsp  0.26 tbsp 2.62 g  0.09 oz  0.01 lbs  0.58 tsp  0.19 tbsp 436.41 g  15.39 oz  0.96 lbs  TF = 0.1

I will leave to you which dough formulation you choose to use the next time. However, if you want to attempt a 14” version of the first formulation posted above (for the 16” pizza), it is:
Flour (100%): Water (63%): IDY (0.25%): Salt (1.75%): Oil (1%): Total (166%):
 262.9 g  9.27 oz  0.58 lbs 165.63 g  5.84 oz  0.37 lbs 0.66 g  0.02 oz  0 lbs  0.22 tsp  0.07 tbsp 4.6 g  0.16 oz  0.01 lbs  0.82 tsp  0.27 tbsp 2.63 g  0.09 oz  0.01 lbs  0.58 tsp  0.19 tbsp 436.41 g  15.39 oz  0.96 lbs  TF = 0.1

As you can see, the Lehmann dough calculating tool makes it easy to change the ingredient percents and quantities. In your case, you may want to try both versions (for the 14” size) and see which version you like better. FYI, the above amount of dough for the 14" size (15.39 ounces) can be used to make two pizzas that are just a bit less than 10".
The All Trumps flour you used is a good substitute for the KASL from the standpoint of protein content, hydration, etc. Some members who have used the All Trumps flour have commented that the finished crusts based on that flour have not had as deep a color as the crusts made using the KASL. I was hoping to see your photos to see if you experienced the coloration difference.
BTW, you don’t have to limit yourself to the paddle attachment. If your KitchenAid mixer has a spiral hook, you may want to use that for the bulk of the kneading. My mixer has a much less effective Chook and I use that in addition to the paddle attachment.
From your comments, it looks like you achieved a dough with a lot of bubbles. I suspect that that was the result of using a lot more IDY than originally intended. If you reduce the IDY to 0.25% (by weight of flour), I don’t think you will get the same degree of bubbling. Some members love the bubbles, so if bubbles are what you like, then you can use more IDY to help achieve that result.
I think you will find that your doughs and pizzas will get better with more experience. If you also learn how to use the Lehmann dough calculating tool, you won't go back to the old methods (using a hand calculator or spreadsheets). It will save you an enormous amount of time and effort. You can also use the Lehmann dough calculator to calculate ingredient quantities to make just about any dough that includes flour, water, yeast, salt, oil and sugar.
Peter