Perfect control bars, unsinkable ships, no thank you.
Options = common sense.
Not much else to add.

haha, everybody got this figured out now?

releasing a bar onto a single outside line (removing all tension from every other line) will disable any kite. it doesnt hurt in any way to have single line attachment points on your outside lines. disabling onto an outside line usually does make a nasty mess of your lines, and is generally not re-rideable from deep water. (some kites behave ok disabled onto an outside line, many flip and twist badly, some so much that you can barely call them disabled)

it does seem like some people dont get that many bars incorporate a single front line disable system, which allows the bar to slide as far up one of the 2 centerlines (on 4 line bars) as necessary to take all tension off the 3 other flying lines. this has the same (in fact better) "flag-out" effect as a single outside line system. a 5th line is also a single centerline system which takes the tension down to a single line and completely slacks all others. single center line systems can be mounted below the bar and still have this functionality (the fifth line was the first like this, then SlingShot CSS for 4 line bars ((i believe was the first)), and now many others.)

those systems are different than a double centerline system, which keeps tension on both front lines while slacking the 2 back lines only. (how effective those are at actually disabling a kite is debatable), but there is no doubt about the effectiveness of any single line system, especially single centerline systems.

so why have an outside line leash attachment point? back-up. although it is highly unlikely a person could effectively use it in a high speed powered "emergency" situation when they are already leashed up somewhere else, it is an option if you know your other leash system will not work (broken 5th line), knot or tangle in your centerlines that you believe will prevent your bar from sliding up a single centerline, or a maybe you rolled through your lines in a weird way and looped centerlines around the bar in a way that would prevent a centerline system from working.

it should be realized that if you go to release your harness loop and disable a kite onto an outside line, your leash must also be released from wherever it was attached (or moved to the outside line you are disabling the kite onto).

now, what is a "mini fifth line" is the real question. thats a stupid term, and everybody has a different definition for it. i never know what people are talking about when they mention it, and wish people (and kite companies) would cut it out.

Say you're buying a car and the vendor is asking you if you would like to have an extra spare brake in case the main one stop working. Will you say "no thank you"?

I hear ya on the number 2 option

I think most manufacturers agree with you there since more and more bars are being produced with out the OS handle? I'm not sure if that's the case or not... probably 50 50.

In any case I prefer to have an OS handle in case my 5th wraps around my kite. Doesn't happen often, nothing to do with how crappy my bar is... it's just a pitfall with the 5th line safety system.

I'd probably say no.

If extra spare brakes is better, how about instead of two brake pedals you have six brake pedals. How about extra gas pedals too while we're at it. Two or three gas pedals, five or six brake pedals, that's a car with a lot of options.

I have oh shit releases on all my bars btw so I don't think they are evil. I just like a simpler bar.

That's a funny analogy but not a good one
All cars have a spare brake ... it's called a park brake.

You have to compare with the airline industry... they have redundancy I'm sure of that.
That's all it's about... built in redundancy.... you can take it or leave it.

I know of someone who's a lot happier today because their bar had "redundancy"
I'll put up with the hassle of redundancy safety... you might not... thankfully we all still have a choice

Options galore... get something that works for you... especially as the winds pick up.... that's when it all happens.

I suppose to each his/her own. I want OSRs.

I use 5th line but wouldn't use a 4 line SLE bar without OSR

That's exactly what I'm saying: all cars have a spare brake. Not all the kites have a spare security device. Why should I have to say "no" to OSR?

I hear ya man but I really don't know what you're saying.