The main reason is it was impossible to rationalise the data.
In all the presented data, there are a set number of rolls for each loot tier and each loot tier had to have a reportable outcome. This made it possible to rationalise the data & exclude data points which were wrong/ missing information.
Unlike all the other items, battle items have a “nothing” roll… which means two main things:
I couldn’t rationalise the data & exclude data points which were “wrong”. This could result in skewing of the data as some people miss the “2x” or “3x” under a given item & hence under-report them.
I struggled to get a definite “x” number of rolls per tier…
I do plan to go back and have a look at battle items again but I figured it was low priority as most people hit titans for the Ascension Materials & the Titan Parts; the other loot is more a bonus than anything.