May I answer to myself that linq to sql is more than meets the eye at first glance.
I dare say it encapsulates a handful of patterns including unit of work, lazy loading, identity map and also acts as an aggregator.
With use of an appropriate , generic repository it can deliver but it does not fit well with the request-response messaging service design since it automatically provides master <-> details bi-directional collections. Furthermore, POCO model classes are somewhat useless or redundant since partial classes can provide for business logic and validation.
All in all, linq to sql replaces the need to deploy most patterns by hand not only in the data access layer but also in the model and service layers thus making the contents of this book look outdated and this is probably the reason no answer was given to my initial question.