I think it is just RNG. A tank-friend i have done quite some delves with got cloak after cloak after cloak. In the meantime i am filling my whole gearset with 603’s. My only problem is i got 2 maps and both items i got from it were wrists. I also have a chestpiece.
From your own sample size, the lack of a chest is not “bad RNG” nor is there anything wrong with the loot system that it did not drop a chest yet. It does not guarantee you a chest drop.
Without your wife’s sample, would you have said it would be “bad RNG” too if you didn’t see a weapon drop either?
I know that 2 people experience with droop loot hardly can be called representation of drop loot system pools. I also acknowledge that random drop don’t give any advantage or disadvantage for specific loot type. I only wonder how other players experience with getting chest was. Some players get capes i get all trinkets - maybe there is even person who get all chest hihi.
I got my answer - thanks
The game can tend to get frustrating when you can’t target loot though. By which I don’t mean only having one thing drop when you do X like in PvP, but having a smaller loot table. Like you do a dungeon and it’s got 3 or 4 things on its table and if you just run that dungeon a handful of times there’s a good chance you’ll get it.
Can’t really do that with delves though. They effectively have a daily lockout due to the bountiful system.
This same problem is also why the vault drove people crazy before we got 1 choice of up to 9 options. “Weekly box of disappointment” was actually a very valid criticism that stems from having a loot table that’s much too big.
If you ignore 1H / offhand / 2H options, and just say there’s 15 slots, it’s around a 19% chance not to get a chest piece in 24 runs, so it’s not unfeasible. I seem to be overrun with pieces for the slots I can buy from the renown quartermasters.
I’ve had a pretty even mix over the 20-odd ones I’ve opened. I got a chest last night and have had two 2-handed weapons. Haven’t had my bis neck or trink yet though.
IMO if you are spending currency ( coffer keys ) then you should get a choice otherwise it’s a waste of a key…
RNG to get a key then RNG again for loot /sigh
Beside 22 isnt nowhere near a sample size that would be needed to even come close to a conclusion, your sample seems really balanced.
Dont see why you thought there could be something wrong with the loot table.
You also need to seperate drops from their type.
There are more trinkets than chest armor for example in the loot table. So you have to list all items separately, not their categories.
over 15 years in WOW (20 with breaks) 
