I've done quite a bit of repair, modification and design for heavy equipment and their accessories, and for the most part you can tell right away which machines have been abused and which ones have been kept within their design limits. I have found that no matter how strong or well designed a tool is that someone will be able to push it past its limit and destroy it, especially if the tool user lacks sensibility or responsibility.
   depending on the age and hours of the machine the cat 345  is in the half a million dollar range, so my question is does the owner know that this is being done to his equipment? if he doesn't perhaps someone should be kind enough to tell him. and if he does thank our lucky stars that their are idiots like this out there to help keep us employed.  from what you described there will be a lot of repair work to be done on the machine, i am sure some owners of heavy equip would hand out a beating along with walking papers for such a behavior.
     the list of repair solutions in the last thread were right on the money so at least there was a great opportunity for learning provided by the guy using an excavator bucket as a hammer
darren