Lemee get this straight.
Somebody put their kid through swimming class, then the kid showed how slow on the uptake he/she was, and did exactly the opposite as what the class showed, or simply what he wasn't supposed to, and drowned?  And a parent is claiming the class doesn't work?

Same thing is claimed about gun safety classes.  Somebody might want to question all education to children everywhere, since they think the kid won't absorb any of it.  If education about guns and pools doesn't work, how can any education work?

Conclusion?  A grieving parent is looking for something to on which to pin the blame for the death of their kid.  Dead children are always unfortunate, but how many people know that families used to have a whole bunch of children, knowing that many of them would never see adulthood?

The classes just buy the kid a few seconds extra before the negligent parent realizes the runt is in the pool.

My parents did not swim and had a major fear of the water.  I took lessons as a kid and followed all the way to my life guard patch.  The chicks dug that patch when I was a kid.

Knowing how to swim has saved my life more times than I can count.  Formal lessons taught me to not only save mine but others and am convinced others would not be breathing now had I not taken the lessons.

Most drownings around here are not from swimming but from falling in either boating or just slipping.  Panic is what kills in water.

With my own son, I have noticed that at first children do become over confident and can put themselves in real danger fast.  This is a real concern with the younger the child and like other posters have indicated it is the responsibility of the parents to drive this home. With this in mind, I can not recommend lessons for the very young.

My kid is a "River Rat" and spends every waking moment in the water but takes water safety as serious as he does gun safety for the end result is the same, death.

I would have drowned in the 8th grade had I not known how to swim. Yes, it saves lives.

 Learn how to swim is a must.  You can take care of yourself if sh!t happens, and you have  a chance to help other one way or another.
 Of course, it's an on-going swimming lesson, just because you can swim that does not mean you won't be drown--and kids need to understand this.  The best way is to give example why it's so, such as cramping, losing consciousness when falling off the boat,etc....
 Two real life lessons:  An boating accident happened a wk ago in a local newspaper--I can't remember where it happened.  There were some 20 people on this capsided boat (probably too many people on the boat), and 6 or 7 people survived because the survivors happened to wear lifejackets.
 Another story:  at a local lake in DFW area about 1 yr ago.  This guy disappeared after jet skiing, they found his jet ski but not his body without the lifejacket until the next day.  The authority and his friends thought that he might have fell and hit something and lost consciousness.  He was a very, very good swimmer also.