Petty details or vital issues?

Being able to observe other teachers in action opens up new horizons for me. It makes me reflect on my own teaching, mainly because it helps me understand things which I wasn't even aware of before. I encourages me to think about small details, but it also gives me a general picture of what good teaching means to me.

It was already before this particular lesson that some disturbing ideas had been swirling in my head. Let's not beat around the bush. I'm aware of the fact that there are some important issues the observer is bound to focus on during an observation, such as interaction patterns, collaboration, eliciting, TTT, timing, error correction, feedback, assessment, classroom management, seating arrangement, etc. What I'm not really sure about and what slightly worries me is what the observer should actually ignore. 

Let's say one observes quite an experienced teacher. By experienced I mean that the teacher has been in the profession for some time now and thus she knows what pitfalls and dangers await her in the classroom. She knows how to manage the class, how to deal with discipline problems, her command of English is pretty good, and she's very confident about her teaching skills. 

Let's say that during that lesson (a class of intermediate young adults), I notice some minor issues, listed below in no particular order:

1) T makes minor errors such as, troubles instead of trouble, or wrong word order in indirect speech. 
2) T doesn't finish her sentences.
3) Apart from giving clear instructions, T uses lots of redundant, barely audible language.
4) T asks Ss to complete a gap-fill during a video projection but switches the lights off so that it's completely dark in the room. 
5) T openly ignores a S's open reluctance to complete a task. 
6) T overuses one particular word in order to praise or motivate. 

It's crystal clear that the above issues don't tremendously affect the quality of the lesson, or more precisely, the quality of Ss' learning. So my question is, if I should mention them to my colleague at all (provided she is willing to listen). Why am I not so sure? I suppose it's because each of the points may have more than one scenario. 

ad 1) 
Scenario 1: T obviously realizes that this is not correct and this particular error was just a slip of the tongue. She is unlikely to say it again even if you keep it to yourself. 
!Scenario 2: T does not know that troubles is not the plural of trouble in the sense of problems. Nobody knows everything after all. However, some Ss may be familiar with this tricky vocabulary item and they may feel their T is not competent enough, even though they won't say it explicitly. 

ad 2) and 3)
Scenario 1: T is only nervous and this is a way of easing the tension. Normally, she speaks fluently, without redundancies or other embellishments. 
Scenario 2: T is/is not aware of this irritating habit but apart from the observer, nobody really cares. 
!Scenario 3: T is not aware of this irritating habit but Ss are, and if the observer told her, she might think about it and finally try to fix it.

ad 4) 
Scenario 1: T didn't realize this but this situation is unlikely to happen again. It actually happened on a very cloudy day. Normally it's not so dark in the room so Ss can see the handouts clearly even when the lights are off. 
Scenario 2: T realized it but didn't want to change the course of the activity/flow of the lesson because she was being observed. The chances are that this won't happen again under normal circumstances. 
!Scenario 3: T knew that it was too dark but didn't think it was a problem and will allow this to happen again. 

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Scenario 1: T didn't find this incident important. This was just sporadic. Normally the student works well; today he's showing off though. 
Scenario 2: This happens regularly and T normally deals with the problem. However, she didn't want to make fuss about it because she was under time pressure (and being observed). 
!Scenario: 3: This happens regularly but T doesn't want to deal with it because it keeps her from doing more important stuff. 

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Scenario 1: The observer is a nutter. Nobody else cares or even notices. 
!Scenario 2: T doesn't realize this but Ss find it irritating and ridiculous. 

When observing a lesson, one never knows which option (scenario) is relevant and worth mentioning and elaborating on. I put exclamation marks next to those options which I think should be dealt with during the feedback session, even though at first sight these issues seem unimportant. I'm a perfectionist and I tend to record every petty detail. However, this can turn out to be really irritating and frustrating for the observee, so I tend to be really cautious before bringing the issues up. As with language learners, it's better to elicit first and then present, i.e. to ask about the context and circumstances and then draw conclusions.