We now know that Head injuries don't all heal, but create possible lasting serious damage. This leads to possible even less people wanting to play Rugby

The other game has trialled games in which tackling is only allowed around the waist. This reminds me of (many) years ago when a lot of tackling was around the waist, something not often done now as players are seemingly taught to tackle at chest level to stop the ball, and others pile in to slow the PTB up, all increasing head contact risks.

When I see lads being taken off concussed and worse still when it's playmakers like Kevin Brown, for the umpteenth time, it really makes me think how can we go on like this. Well the point here is the trial games with no tackling above the waist were apparently a great success for more open rugby and less serious injury. We should try this ASAP.

Did the study that came with this also note a rise in tackler concussions as a result of contact with the hips and knees of the ball carrier?

I've not seen any detailed study, albeit even a trial game would at least indicate whether the injuries would simply be "different". I go back a long way and can remember when a lot of tackling was about "taking his legs" on the basis a player could not run without them. I also remember some players who would specialise in diving into leg tackles which made them look spectacular.

Maybe it's a "the good old days" thing but I do not recall there being so very many head knocks years ago, I do remember Chris Sanderson and Mick Shoebottom's injuries.

It is a bit like the argument for daylight saving. We were told that during the war when daylight savings had been tried there were fewer people killed on the roads during the lighter evenings in winter. What we were rarely told was that even more people were killed during the darker mornings. You pays your money and takes your choice.

As has been suggested there seems to be real number of head injuries caused by collision and clash of heads between team mates when tackling an opponent. None of these tackles appear to be above shoulder level.
Perhaps the punishment of an automatic sin bin for tackle to the head, direct or via the chest or shoulder. Obvious red card for the worst of the offences.

As far as I know the trial was quickly stopped and deemed a failure.