Edit: I've chosen to do a thorough review of distributions for rolls shown in the UI as Low Ground, but get rolled at normal. And rolls shown as normal that the combat log rolls as high ground.
Here is the data for "UI lowground & Combat Log Normal":
I used the bugbear assassin and scorching ray to test.
UI for Scorching Ray, Gale's position relative to bugbearScorching Ray 1Scorching Ray 2Scorching Ray 3I did use different sections of the bugbear, stomach, head, shoulders, etc. The UI and Combat Log were consistent in what they showed.
Here is the data after 156 scorching rays on the bugbearAverage: 7.8
Standard Deviation: 2.5
All frequencies were within two standard deviations.
The important takeaway is the shape of the histogram, it doesn't match what we would expect for disadvantage, it is a lot closer to what we would expect with normal attacks.
The surprises are how low 6, 7, 15, and 18 are but it would also make sense to weight the dice against four outcomes, to increase the change of 10 and 11. (Their frequencies were still within a normal distribution.)
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Here is the review of attack rolls where "UI doesn't not show High Ground or any advantage, but the combat log has awarded advantage on the attack roll".
The frequency is in line with what we would expect to see with attacks rolled with advantage.(This was done at the save file back at the Dank Crypt, N=42)
