Tim... You are correct in that the issue only occurs when the items share components and I welcome your fresh and simple approach as to a solution. The problem is that most all BoMs will have Labour and/or Overhead and this causes grief.
The only other piece is when we have Labour and/or Overhead at the parent part level (not BoM) as this data gets lost when WO items are received. Easy to prove... Create a WO with an "M" part with BoM and no Labour and/or Overhead at the parent level. Receive the items and check inventory value. Now add Labour and/or Overhead at the parent level and repeat the process and you will see inventory value is off because Labour and/or Overhead at the parent level are ignored during receipt. See here:
http://www.weberp.org/forum/showthread.php?tid=8253
Hence my request to make Labour and Overhead Std Cost fields hidden for "M" parts with BoMs. Or... Exclude parts from WOs that have Labour and Overhead Std Cost values assigned... Like I stated earlier... Many Use Cases to consider...
