A very nice feature of the Notes C++ API is it's ability to work simultaneously with the Notes C API. You can easily pass important information about databases and documents between the two APIs and work on the same data. Why would you want to do this ? Well, remember that you can do almost anything with the Notes C API. Things not yet exposed in the C++ API can be achieved with the Notes C API. This brings me to a very important understanding
Important concept! Combine! combine and combine
The true power of many applications lies in the combination of techniques utilized, and the true power of Notes API development lies in combining the different tools you have at your disposal.
The most sad comment I hear is "Now that I've learnt LotusScript, I'll start using that everywhere". This comment reveals immature understanding of the fantastic possibilities in the different tools such as @Formulas, C and C++ APIs amongst others. An application containing solely LotusScript will either be a very very small - or - a tragic application loading the Domino server with unnecessary burdens. A more seasoned Notes developer can see the forces and weaknesses in each of the tools, and select correct tool according to tasks being solved. Never, never say again "I've stopped using @Formulas" again :-)