I personally think you do not learn in hard sparring where you are afraid of getting hurt. I do not think it is an enviroment where one can progress thier skills (many fighters look the same year after year). Also the Thais 'play' in sparring and thier skills are hard to match.

The Thais do get to fight way more and as they start out it is a different atmosphere...

I think someone should build slowly at a pace and power level that they are pretty comfortable with, slowly pushing it a little. Eventually testing now and then to see how they react with harder shots (I don't mean out of the blue hard shots but planned days of picking it up a bit).

Once comfortable going hard I don't think it needs to be done all the time.

1-risk of injury that makes one have to step back from training
2-again, one is in a very sympathetic state, fight or flight, and though it may have its time and place it is not conducive with learning (change)

Do what you've always done and get what you've always got..
Was it Einstein that said something like 'If you do something the same way and expect a different results its a sign of insanity."?

Sparring hard doesn't allow for awareness-awareness is always nessasary for a conscious effort to change.

Playing, besides fun and positive (great places to be for learning)-takes away the fight or flight response-allowing one to focus on change and improvement.

Constantly training in a state of fear or fighting for your life so to speak trains you to be in the same state in the ring IMO

That means you are more likely to revert to survival and maybe be less able to access your deeper skills and abilities.

Thats my opinion on sparring hard...

How bad is sparring... how hard how often?
Reality will probably be its realative to how much your individual body/brain can take before degenerative changes are noticable...

My training partner told this from Sit Yodthonn (anyone been there or there now might be able to add...?)

They use to spar hard with just hands (I think just hands). The kids would miss school sometimes from not feeling well etc They stopp sparring hard and they had way less concussions and KOs from the fights-easily noticable difference..

This is second hand from my training partner (we have no gym and often its the two of us so...)

I do spar for sure... I don't like going too hard too often cause I actually care about my well being and I know fighting isn't all there is in life. I also would like the choice to be able to fight for a long time to come.

I don't see people learn alot in hard sparring-I see them being programmed to be scared and often shying a bit and or you see though guys that can take a beating... well taking a hit is good and all but I really don't think that gets stronger and stronger the more you take 'em (maybe I'm wrong).