I understand, I do. The excuse "but he was injured..." comes with the issue: how often is he injured? Kyrie is injured a notable amount, though the degree to which he is injury-prone is probably overblown. Excluding this season, Kyrie has played in 70 games in two of his first 4 NBA seasons, and 50 games in all of his first 4 seasons. He is on pace to finish this year having appeared in 50+ games, as well.
Ignoring that -- and ignoring that Kyrie is about to turn 24 while IT just turned 27 -- I think tarheels hit the nail on the head: when Kyrie is healthy, this one goes to Kyrie.
In last year's playoffs vs. the Celtics, Irving averaged 23.3p, 5.0r, 4.3a, 1.0s and 1.0b on .435/.480/.808 shooting splits (.578 TS%) in 40.6 mpg. He had ORtg/DRtg splits of 126/104. IT4 averaged 17.5p, 7.0a, 3.0r, 0.8s and 0.0b on .333/.167/.969 shooting splits (.514 TS%) in 29.8 mpg. He had ORtg/DRtg splits of 101/114.
So, OK, fine. IT4 was still adjusting to Boston's system and approach, wasn't playing as many minutes, and just had a bad series in which he couldn't hit the broad side of a barn for 4 games unless he was at the charity stripe.
This season is undoubtedly IT's breakout season. Irving entered the season injured and returned mid-December. Giving Irving 2-3 months to regain form, he should have started approaching peak conditioning and production around the start of February. In his last 15 games (since Feb. 3rd), Irving has averaged 20.3p, 4.5a, 2.1r, and 1.0s on .475/.357/.897 shooting splits in 29.5 mpg. In IT's last 15 games, he is averaging 20.8p, 7.0a, 2.7r, and 1.2s on .413/.338/.888 shooting splits in 32.2 mpg.
I'll agree, IT4 certainly looks like the superior player in that stretch. But that 15 game stretch doesn't offset the dominance Kyrie has proved capable of when healthy. IT will have to be the superior player to Kyrie for at least 1 whole season before I begin to contemplate which player I'd rather have.
IT4's contract makes it an interesting conversation, but one ignored aspect of the financial comparison is that Kyrie is locked up until the summer of 2020, starting this season at $14.75m and ending at $19.17m in 2019-20. Kyrie will be 28 when his contract expires. IT4's contract, however, will expire after next season (summer of '17), when he will be 28. How much will he command on the open market?
All things considered -- age, natural talent/potential, medical history, contract -- I go with Kyrie without blinking. He has the potential to be one of those era-defining scorers, like AI, Kobe or Steph. We'll see if he fulfills it.