I would recommend trying the .plist first. Reinstall only if the .plist method doesn't work for you. There are two reasons:
1. It is much faster. It takes all of 60 seconds to do it
2. It probably preserves much more of your customizations than re-installing everything (this is an educated guess only, since I did not test the re-install method)
If you have lots of time to spare and do not mind loosing customizations, by all means, use the SMM (Standard Microsoft Method = reinstall everything ... ;-) ).
As for the other part of the comment, the "too many versions" is at best a lame excuse. Even more so when Apple FULLY controls the entire chain: hardware, OS and application. I can see this excuse being somewhat acceptable when we talk about Open Source/Linux or especially Windows, where nobody really controls anything. Even there, I would expect such severe defects to be caught in the developer's QA phase.
This is not Apple bashing. It is a flag raised after watching this trend for quite some time now. We had major issues after the Lion upgrade and it took us a long time to make Aperture usable again.