@Tago-Mago I have possibly the nerdiest and the most thorough size-checking process of anyone on the forum which is why this one particular order is troubling me 
I have a spreadsheet that contains the sizes of every item I own (15 of which are IH items), along with my ideal size for each measurement. I then take the measurements of items I'm looking to order and key them in, and the spreadsheet tells me how much each garment deviates from my ideal size (in inches and %), as well as what other single existing item I already own that is most similar in size to the item I'm looking at purchasing.
Where this system fails is for an item like the IHTL-1213...
- I have this shirt in L in two other colors
- For the Indigo color, the size chart seems to indicate I should wear an XL, because the P2P measurement is 21.7" (my ideal is 21.5)". My large versions of this shirt in White and Black are 21.3 and 20.9" respectively. For this shirt in Indigo the size chart says 19.7" for a Large, which is more than an inch smaller in width than the other colors
So I look at two stockists who have models wearing this shirt (below):
Franklin: The model is 5'10", 175lbs wearing a large. Shirt fits the model perfectly (other than shoulders being too wide)
Withered: The model is 6'0", 175lbs wearing a large. Shirt fits the model perfectly (again, aside from the shoulders)
I am 5'9" 162, so naturally a large would be my appropriate size right? It probably would be a bit too big, since I am smaller than the models. Nope - the IH measurements guide indicates I might not even be able to get a large over my chest, and I should order an XL. Make it make sense...
I ordered the XL but I'm reasonably certain I should have just ordered the large. The XL surely cannot be an inch smaller than the same shirt in a Large in a different color...

