snip
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Are you sure they were Phillips and not Posidrive screws?
Only "dubbed off" end I have seen were only Phillips, the pointier ones
were Reed Prince. So you are saying Posi Drive are shorter?
George V.
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This is not a unique problem and is far more frequent in assembly
operations than it should be.

Thre are three common cruciform drives in common use.

Reed & Prince with very thin "wings" and a long sharp point --
commonly used in the US only on golf club face inserts.

Phillips with slightly thicker wings and a blunter point that
still is sharp although may be slightly rounded. Sides of the
wings tend to be slightly tapered increasing tendency to cam out.
Generally no marks on top of screw other than cruciform.

Posidrive with thick wings, blunt point that is dubbed off more
or less square on end. Top of screw will generally have light
"x" between the cruciform drive slots. sides of cruciform are
parallel and have no tendency to cam out.

see http://www.justbrits.com/pozi/pozidriv.html

Given the problems you seem to be having, you may wish to
consider another head/driver style such as Robertson/Skrulox.
see http://www.robertsonscrew.com/

If you have more than minimal parts volume you can most likely
realize significant savings in scrap/rework and labor by
contacting a reputable fastener distributor. They can evaluate
your needs and provide the lowest overall cost fasteners. You
may even save on worksman comp by eliminating stab and repetative
stress [carpel tunnel] injuries.

Hope this helps.

GmcD