Great article, both on recognizing what a bookmark is and how to handle it. However, in your text you state that there are 4 methods to counter but only list 3. What is the other one?
Resolving bookmark lookups
Once you discover the columns responsible for a bookmark lookup, you will need to consider one of four methods that are available to resolve the bookmark lookup.
1. Create a covering index
2. Remove the offending column
3. Convert a non-clustered index into a clustered index
Buy the ticket, take the ride. -- Hunter S. Thompson