You make some good and valid points. Perhaps the following comments based on my experience will offer some guidance.
Scales. As between ounces and grams, I believe that grams are more accurate. By that, I mean I can measure grams more accurately on my scale than trying to split 0.05 ounce increments, although with experience I have managed to come pretty close. However, trying to achieve great accuracy with digital scales for small amounts of lightweight ingredients is prone to error. Unless you have an extremely accurate scale or a specialty scale (like the one mentioned below), you are unlikely to be able to accurately measure small amounts of lightweight ingredients. Tom Lehmann once told me in a Q/A exchange that “even a slight breeze on the scale can upset your scaling accuracy by a significant margin.” Also, the weights of ingredients like sugar, salt and yeast can vary, due to such factors as humidity, moisture and age (e.g., drying out).
For the above reasons, I usually use conversion data for converting between ounces (or grams) and volumes for the lightweight ingredients used in small quantities. The conversion data comes either from efforts of our members, including me, who have weighed one-cup quantities of ingredients like salt, sugar, yeast, and oil and converted them to one-teaspoon quantities, or from the information provided on the labeling for packages or bottles of such ingredients. However, even the conversions can be inaccurately used because a weight might be converted to an oddball volume measurement for which there is no standard measuring spoon in most homes, such as 1/16 teaspoon or 1/6 teaspoon. This forces us to make our best estimates.
I might add that there are specialized scales for weighing very small amounts of lightweight ingredients. One of our members, pftaylor, has a Frieling AccuBalance 401 scale that has a 250g./8 oz. capacity in 0.1 g./0.005 oz. increments. I suspect that using such a scale will produce more accurate weight measurements than the conversion data I use, but the differences are unlikely to materially alter the outcome of any dough that I will make. So, my advice is not to worry about trying for extreme accuracy for small amounts of lightweight ingredients. You can’t achieve it as a practical matter, so close is good enough. If you were a professional pizza operator making hundreds of pounds of dough daily, then you would be able to achieve greater accuracy because you would be using much larger amounts of everything and the error rate will be lower as a result.
Stand Mixers and Mixing Speeds. My KitchenAid stand mixer has ten speeds, labeled Stir, 2, 4, 6, 8 and 10. There are odd-numbered speeds, they just aren’t labeled. In my early days experimenting with the Lehmann dough recipe, I used speeds 2 and 3 more than I do today. I now also try to keep the total knead time down as much as possible, to around 8 minutes, so as not to overknead the dough and to rely more on biochemical gluten development. So, today, I am more likely to use the Stir, 1 and 2 speeds, and occasionally a few seconds at 3 speed at the end of the kneading process if the dough looks and feels like it might need it. Using 13-15 minutes of total knead time and speeds 2 or 3 for a good part of the total time is likely to result in an overkneaded dough, and this will show up in the form of a tight crumb in the finished crust with few, large, irregular-shaped holes, even though a high hydration level is used.
Autolyse. I have experimented on occasion using autolyse (the classic Calval autolyse) with the basic Lehmann dough recipe. However, I have not personally achieved significant advantages to suggest that I should use it all the time in the basic Lehmann basic dough. My experience has been that the crumb takes on more of a bread-like character. I might also mention that one purpose of using the autolyse is to reduce the total knead time. So using an autolyse with a long knead time somewhat defeats its purpose and is likely to contribute to a more dense, less porous crumb.
Extensibility of the Lehmann Dough. As fond as I am of the Lehmann dough, my experience with the Lehmann dough is that, in a home setting at least, it is temperature sensitive and sometimes prone to above-average extensibility (stretchiness). I have reported on this on several occasions. The Lehmann dough likes cool temperatures—in the water (just cool enough to ensure a finished dough temperature of around 80 degrees F) and low cooler/refrigerator temperatures (between 35-40 degrees F). It also doesn’t need any added sugar, although it can be added, at around 1-2% by weight of flour, if the dough is to go beyond 48 hours or so. You indicated, abc, that you used malt. You didn’t indicate whether the malt was diastatic or non-diastatic. The diastatic form of malt provides additional amylase enzymes to help extract more sugar from the starch in the flour. Most bread flours today are already malted at the miller’s so it is usually not necessary to add more since this can lead to a more slack dough. If the malt was the non-diastatic form, it offers no additional amylase enzyme and behaves essentially like any other sugar. Like any other sugar, if used in excess of what the yeast really needs, it can adversely affect the fermentation process and the outcome of the finished product.
My best advice for the next Lehmann pizza is not to worry about the small weights of ingredients, stick with the 63% hydration level (at least for now), cut back on the mixing speed and duration of knead, try to keep the finished dough on the cool side as much as possible, and dispense with the autolyse and malt. You can always decide at a later date to reintroduce either the autolyse or the malt or to reduce the hydration ratio. If the extensibility is still too high after these changes, you might consider using the dough a bit sooner next time, say, 16-18 hours.