I believe I follow your response, though does it consider those who do not have a full year of coverage or coverage? I will try to better explain --- ok, here we go . . . 

Line 3 (#5) If you were not an eligible individual on the first day of the last month of your tax year,

use the Line 3 Limitation Chart and Worksheet (in these instructions) to determine the amount to enter on line 3. (See (6) in this list.)

***The taxpayer had coverage Mar – Aug (6 mos.) so, he was not covered on 12/1/23 and the spouse had coverage Jan – Feb (2 mos.) also not covered on 12/1/23 *** The limitation worksheet prorates the contribution limit with the TP eligible to take $3,875 and the spouse $1,292 for Line 3

using worksheet for line 3:

Line 6 f8889-Enter the amount from line 5. But if you and your spouse each have separate HSAs and had family coverage under an HDHP at any time during 2023, see the instructions for the amount to enter:

If you are not treated as having family coverage for each month, use the following steps to determine the amount to enter on line 6 (summarized)

1. Refigure the contribution limit that would have been entered online 5 if you had entered on line 3 the total of the worksheet amounts only for the months you were treated as having family coverage when refiguring line 5, use the same amount you previously entered on line 4.

In this case f8889 Line 4 is blank – no MSA’s --- so Line 3 carries to Line 5

1. Divide the reconfigured contribution limit from step one equally between you and your spouse unless you both agree on a different allocation.

I looked at different splits between the total contribution amount (3,875 + 1,292) or $5,167

My understanding is that if either of them were covered on 12/1/23 they would be eligible for $7,750

1. Subtract the part of the contribution limit allocated to your spouse in Step 2 from the amount determined in step one.

Step one contribution limit $5,167 – spousal portion = $3,875- so, I really don’t know what the instructions are trying to achieve here, except maybe to make sure the allocated amounts do not exceed the total amount of contributions that are available to use as a deduction.

1. Determine any other contribution limits that apply for the tax year and add that amount to the result in Step 3 enter the total on line 6.

No other limits to apply so Line 6 remains the same for the TP [3,875] and spouse [1,292]

This couple does not have full year coverage, so I don’t find they are eligible for the $7,750.