Peer I agree with you. I remember when UML is new in market (2001 for our country) every body start their project from Use-case design and class diagrams then one month after first design, diagrams are something absolutly different.
Currently I use UML modeling for better understanding the functionality of operational system(reverse engineering) and documentation.
1- We have an enetrprise software handedover from other team I think it helps a little more when we have all class diagrams on paper.
2- My university Diploma thesis is finished I should fill about 100 A4 paper, so UML diagrams can occupy near 10 pages >
For that sort of use the modelling component in RAD is OK. You can't really use it to create models, but if you have existing code and you want a way to visualize it its OK. You can even run a debugger visualizing the path you take through the code as a sequence diagram.
As I am using Rational Rose. I found it is easy to do reverse Engg. from here. But limitation is like you can just make reverse engg. of classes only. Not any other Diagrams like (Sequence Diagram etc.)