The reason these engines failed is MORE COMPLICATED than the fact they
were at 41,000'. These planes can fly at 41,000'. What happened is
related to how they got to 41,000'. They got there by exceeding the
maximum climb rate. The plane was empty so it climbed very fast. But
due to some complicated factors, the engines cannot go to that altitude
that fast. They overheated. This was a published limitation. They
exceeded it. Even my simple explanation is not adquate as it is more
complicated than this. This is due to the fact that I don't completely
understand it either.

And to answer your question, yes it is safe to operate at max altitude,
if the pilot follows all of the correct procedures when operating the
plane and if the plane does not have damage and has been maintained
correctly etc. The plane has been tested there, and higher still, so
there is some safety factor.

These engine failures were from some complicating factors. Not just as
simple as flying too high.

One word of advice. Don't get your accurate information from the
newspapers. You have to go deeper to get accurate information.