i guess we'll have to agree to disagree. the load index is decided by the code FOLLOWING the tire size, not IN the tire size. according to a quick google search to verify, the P or LT is there for the same reason as C (commercial) or ST (special trailer service), to explain the use of the tire, NOT the load rating. the load rating is not displayed in the tire size (example LT285/75R16) as read on the tire. its a secondary set of number/letters.
ill even include this right from tire rack:
"Using a tire size P195/60R15 87S as our example, the 87S at the end of the size represents the tire's service description. A service description identifies the tire's load index and speed rating. Service Descriptions are required on all speed rated (except for Z-speed rated) tires manufactured since 1991."
sooooooo anyways.... again, i was just curious as to why they put a p anywhere near this tire on their website because ive only seen "P" as a representation of the tire being meant for "passenger" use. yes, a "passenger" rated tire will have less of a rated load index, but it is NOT there to identify the specific load index of the tire, only the intended use.