Every few years I try to tackle an assembly by creating one multibody part and exporting each body. This method has great advantages in that:
1. A single reference sketch can control features across parts
2. A single feature can affect multiple parts
These advantages greatly ease the process of creating parts that fit together in an assembly. The only problem with this method is that the external references engine is horrible and has been so for the past 10 releases. I always end up regretting using this method in the end.
The problems are as numerous as they are fundamental--so much so that it is absolutely irresponsible allow the user to even create external references. Highlights of my latest experience (SW2012, SP5):
1. Appearances come and go as they please. Usually cured with a program restart.
2. References go in- and out-of-context as I edit the multibody. Usually cured with a program restart.
3. Reference often break, causing me to delete the part file and re-export the body.
4. Sometimes, the exported part is missing features from its source body. This lingers despite multiple saves and program restarts.
How Dessault thinks it can continue to ship fundamentally broken products year after year boggles the mind. Do they know we have options? Have they ever heard of NX? I look forward to lobbying for my company to switch at our next IT review.