Iincidentally Mickey, I personally actually really appreciate the effort you're going to here. It's nice to see, and you may notice that unlike you're mate you haven't been shot down, and that's because you've been careful in your language, from what I can see shown some respect, and backed up what you're saying.
Just wanted to add - why are you using injury time GOALS?
You won't find anyone here who doesn't, through gritted teeth, understand and admit that Utd tend to be fitter than their opponents and have a great skill, not luck, skill at pressurising towards the end of a match - it's practically your trademark. That you score x goals in injury time would never surprise me, and I wouldn't use it to show bias, either for or against.
It's the AMOUNT of injury time GIVEN WHEN LOSING that's relevant, and as I said above, it's already been proven - not guessed, not looked at a few games and you got more in those, but actually proven over a number of seasons, and season by season, that you get more injury time than any other team when you are losing, as I said, it's an average of 20-30s I seem to remember, which doesn't sound a lot, but when you're score as often as you do, or we do, in injury time, an extra 30s or so makes a hell of a lot of difference.
I'd also love to see the stats for 'tight' games - IE, games you/we are losing by one or drawing, then compares those with stats for losing by 2, losing by 3, winning by 1, winning by 2. That would give a really clear picture of whether one team is being favoured in terms of injury time. Still though, I think those Guardian stats were pretty clear.
I haven't read or seen the full debate on here about injury time but it's pretty obvious to me that
a. if a team playing united is drawing or winning they will waste as much time as possible with injuries, substitutions and general slow play - the longer they've been winning/drawing the more time they'll waste adding to the amount of injury time and also forcing the ref to add more time than was shown (if its done in injury time)
b. when united are winning we still tend to play out own game and not waste time as much, we're usually the team putting the pressure on and trying to force another goal no matter what the score (I know there are particular cases when this isn't case but generally it's true)
c. if we do score (which you admit we do more than most) then the goal celebrations will also add on time, plus the inevitable substitution straight after the goal if it's a tight game
d. ferguson (and other managers) make unneccessary substitutions when losing, make them as quickly as possible to get time added on and so a net gain if the sub takes less than 30 seconds.
to genuinely compare the injury times of different games you also have to analyse the number of substitutions, at what time they took place, how many injuries there were and when they were, what the score was throughout the second half etc etc, without those. Any slight difference overall I think can be explained by the 4 points I made above, although you may have information I'm not aware of.
EDIT: I had a look at the guardian article
http://www.guardian.co.uk/football/2009/sep/22/manchester-united-goals-stoppage-timeit does say what that united get more time when losing when winning, logically explainable by what I said above, it also says that there is slightly less injury time at OT than at anfield, the emirate or stamford bridge, without looking in detail at some matches I can't provide an explanation however I would guess that it's explainable by the fact that united waste less time when winning than the other 3 teams mentioned and so overall that results in less injury time.
What the article doesn't do is say what the comparative figures for liverpool, cheslea and arsenal when winning/losing are, without which any discussion is meaningless as there is no way to say if united get beneficial treatment.
The fact that the guardian didn't mention the winning/losing times for all teams (they must have had them otherwise they couldn't have calculated the total averages) means the writer of the article is either
a. stupid - if they show that united do get more extra injury time than the other 3 when losing then they are conclusive proof and give the article far more weight
or b. deliberately withholding information because it doesn't fit what the writer wants to say - far more likely as its the only reason I can think of for not including them.
I'll try and get the stats from somewhere, maybe the bbc have archives of the matches
EDIT2: can't find accurate injury times for anything other than this season, sky and soccernet have some but only to the minute, not to the second and it's hit and miss whether they're done or not so I can't get a comparison, still, everything I've said is perfectly logical and far more reasonable than the explanations offered by some.