You are hilarious.
Is that how you do things?
But I'm on vacation, so I'll play along.
It's already borne out in his numbers, so no need to subtract anything. And to answer your next question, no I don't rate him purely on his away numbers because then he would be closer to Walsh than Ambrose.
So very honestly, if I were to either rate him on his away numbers alone, or "subtract" cheat / umpiring "points" from his home numbers (which isn't beyond reason), he would be below Donald, Lillee, Wasim, probably Holding and Garner as well.
For me he just wasn't as good a bowler as;
Marshall, McGrath, Hadlee, Steyn, Warne, Murali nor Ambrose. You know what, neither does the forum, because that's where they consistently rate him as well.
It also doesn't impact how I view his batting. Even without the no's (which % was so very much higher at home), and a couple hundreds where earlier declarations would have been in order, it is what it is. The numbers are soft and a little inflated. Doesn't make him not the best lower order batsman in the game. Not nearly Gilchrist level, but for 8, definitely. He definely had some really good and crucial innings, but wasn't nearly as consistent as is projected in some arguments. But he was a lower order guy, so wasn't expected to be.
Now where the extra circulars does impact my judgement, and there are 2 of them, and the 1st would just be a me thing as no one else chooses these teams this way...
Are for AT XI's, and even then it's a coin toss between him, Wasim, Steyn and (really should and deserve to be) Hadlee. At face value he's the 4th best bowler of the 4, easily the best batsman, but again arguably the 3rd best with the old ball, and Hadlee wasn't bad there either. But then the question for me is, unless he's travelling with his home umpires, and the camera isn't looking at him, how good will he be compared to the others. And there his away numbers does comes into play, and they aren't nearly as good as the others. You may disagree, but it's a valid point.
The 2nd is overall ratings. On his overall numbers and at face value, he's top 5 all time... He's the 2nd best all rounder of all time. But there was a reason why, even during his peak there was no one calling him the best, and even in the totality of his era he was rated between 3rd and 4th. Everyone knew, and he and Miandad were docked a little for the home advantages. Then the batting average was never quite aligned with the production, and even then it got a major boost near the end of the career. So yeah, top 10 is a fair spot for me, not good enough for you, but we can all agree to disagree.
But that's basically it, they don't factor into by bowler ratings, if it did, he would be lower. And the reason I do being it up (and will bring it up every time you start you bs), is because you consistently go after his rivals and everyone else with exaggerated nonsense... Specifically of late coming up with various caveats, "did they benefit from...", while no one benefitted more from..... than Imran. Yes Kallis's bowling average may flatter compared to his output, so does Imran's batting average. Yes Ambrose's s/r wasn't the greatest, it was the same as Imran's, but he was also the best in his era and was better away from home.
And just to be sure you see I've answered your question, I don't take off cheat points, and he's exactly where I think he should be. If I deducted cheat points, he would be ranked lower.
And even without the home advantages, he's still not a lock for my XI, because Steyn was a better bowler and could also a master of reverse, Hadlee was just better as well and a good enough bat for 8, and Wasim has the variety, best ever with the old ball (with or without reverse), and too was a clutch bat. So no, not because I dislike him for what ever contrived reason you come up with. Even in our last poll he was tied for 4th among the fast bowling options, and well behind the top 3, it's not just me.
And for the record he was an immensely talented bowler and a more than useful lower order batsman. From the history of the game I have only 5 pacers and 2 (possibly 3) spinners ahead of him. I have him as a top 10 player of all time even taking into account the outside stuff, but you're argument to me is that isn't enough and I'm biased against him. None of those are outside the bounds of accepted ratings and higher than quite a few. So give it a rest.