I would say kata will not help you in self defense.
Actual unnarmed techniques are such a miniscule part of self defense that it isn't even funny. Awareness of your surroundings, Common Sense, Avoiding dangerous areas or situations, and avoiding confrontation are so much more of self defense than any single unnarmed technique that it isn't even funny.
People seeking Martial Arts completely as a means of self defense are fooling themselves outright, as the vast majority of it won't help you in 99.9% of your ever day self protection, and it won't help you in 95% of what is considered "Self Defense Scenarios" now a days.
You going to throw a punch or kick at a gun wielding person seeking to rob you?
If attacked by a crazed homicidal maniac, and you are truly in fear of your life are you going to just use your hands?
Myself, despite whatever unnarmed skill I have, if I am fear for my life I am using my gun, my knife, or whatever else I can pick up, and my "techniques" consist of hit as hard as I can with a blunt object, and stick the pointy end in as many times as I can with a pointed object.
Most unnarmed fighting techniques are good for about 1% of self defense, hell maybe even less, as I don't count fighting with drunks, or ego fueled confrontations as self defense.
Understandably I know your stances on kata. However I think that it is circular argument. For example one guy is going to say that by focussing on kata your instructor doesn't know what he is doing, you are going to say he does, etc.
Vice Versa, someone who says they used to do kata and now don't like it, you are going to say that they truly aren't doing the art, or that they didn't learn kata from an instructor who knew what they are doing, they are going to say that their instructor kicks *** etc.
Personally I have some experience with Kata. I feel that it is useful as a conditioning tool, and as a means of defining the mechanics of a technique. All techniques have to be altered from kata, or from how they are taught by each individual period. The entire Bunkai aspect of long drawn out forms is interesting to me, only because of the various interpretations each person has in them.
I see nothing wrong with kata, but I disagree with the "kata will get you there only slower" argument.
Without sparring and contact, no amount of kata will help you. You will lack timing, rythm, and the ability to see openings in defenses, and the application of the technique at full speed against a moving resisting target. However the mechanics of the block, of the strike or technique can be further and further refined in kata to make them stronger, more functional, more natural and not awkward. So that using them in sparring becomes easier, and the techniques themselves are stronger. Adapting them becomes easier because you more wholly understand the technique.
Competetive Judo players will tell you how much more they learned about throws and the art when they started doing kata, (most start at an older age, after they can no longer keep up the rigors of Shiai) Few actually focus on it outside and find out how much it can help their shiai.
However, without the randori or shiai, sparring, or fighting, you won't have the ability to use the tools kata presents you.
You need to develop timing, and autonomous muscle memory that kicks in during fight or flight. You have seen the guys on the verge of losing win it all back with one punch that they threw automatically in reaction to a certain technique.
Not to mention the ability to actually have defense, which you will never get without someone trying to hit you and you stopping them repeatedly.
Kata helps you refine the mechanics and understanding of the technique, but it's application and muscle memory as a reflex has to be built in sparring. Otherwise you won't know which blows an upwards block truly blocks, or when you need to start it in reaction to a punch to actually block a blow, too soon or too late you are getting hit. That kind of stuff doesn't get developed in kata.
But I don't think an entire 100 step kata is necessary for that, but it is a useful way of passing on the curriculum and techniques of the art. The rest (the application of the techniques) varies from person to person as they modify them to work for them.
That is my two cents..
My words and logic are a testament of my experience.