In article ,
says...

I was always taught that to change more than one thing at a time was
unwise. If you do that in electronic design, or software, yu deserve to get
your fingers burned. I suppose its OK if you can test all the changes
individually, but I suspect in this case cost and time are probably driving
the path here.
Unfortunately, quality control can be a nightmare when you are relying on
contractors who, on paper perform to the same spec, but humans make errors.

True, but in this case the failed helium tank strut was a clear single
point of failure which was easily solved. That and it was not really a
design variable; it was much more of a quality control problem.

Also, changing more than one thing on a launcher is quite common.
Saturn V evolved quite a bit over its short lifetime, to the point that
no one Saturn V was quite the same as any other.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer