Hertao, I am sorry to say but I believe that you are not understanding quite well what "training methods" really means to some os us...
It means that, like in any sport, you define technique according to what you, along with others, using environment, time, natural skills, and a lot of "honesty" and "objective reasoning" search to achieve.
An example of another sport: I believe you call it High jump bar. For us is "salto em altura".
Well, anyway, the way people jump over the bar changed with new presentations of styles, until in 1968, I believe, a guy called Fosbury researched on an University, and "created" the Fosbury flop, where you pass first the head and shoulders, and then the rest of the body. That style became, at some moment, the only style. Why? Because any athlete using this style improved his own outcome, much better then using the old styles. So, being a sport, someone have tried, and tried, and discovered a good way, and tested, and a lot of people tested, and... It became anyone's style, because everyone has the same purpose: To have the best result, jumping through the bar.
In martial arts, this is not true. Everyone, almost everyone actually, has one soul purpose: To make clear, to the world and himself, that what he choosed to train is the correct thing to train. So, when some people insert sparring in their practice, they only do so to justify what they train, so they lack objectivity and honest reasoning. They also lack the key of that "special locker room" where we are suposted to "keep the ego", while training. Even in TMA, I saw a lot of people training stuff, and then proving their stuff correct, by putting some helmets and using some soft sticks, "suposedly" to give realism to the thing, but if you look closely to many of them, you will observe that even going full out in beetwin, when it is the moment to prove their point, on efectivness, the velocity is there, the striking force may be there, but the resisting factor decreases...
So, in short (english is not my language, so when I write directly in english, most of the times I get confusing results, in terms of writing...), I believe that proper, honest and objective training methods, with the goal of efectivness always focused, WILL change what you train.
It's not the sparring. Is the way you sparr. If you sparr to prove what you already believe is right, most of the times you will, even without realising it, find a way to prove what you believe in.
If you, by the other hand, believe in sparring, and believe sparring will help you define if something you think (ratter then "believing", a very different thing) capable of being efective... is or is not, you will, eventualy, decide to "jump with the head and shoulders first".

Just my thoughts...