Rational Team Concert, or RTC for short, works best as a full SDLC development, test management, and release management suite. When you have your software architecture and project work management integrated into it, and have tasks assigned and processed the way they should, it really gives the management and end-users great visibility of their projects and where they are in their various phases. However to do that requires that EVERYONE learn and use RTC fully. And that is just way too high a barrier to entry for many places to surmount as they need to continue DOING rather than learning, which is admittedly inefficient and stupid and leads to bad practice becoming ingrained in an organization and thus institutionalized. However, until senior management grants enough time for people to learn to RTC fully as it should be, which is the role of the braver middle managers to push, i.e. be real leaders instead of yes-men goons for the seniors, it a such an easy set of tools to misuse, abuse, waste the potential of, and otherwise turn it into a mediocre partial solution as part of your kit for the SDLC.
That said, the following things are good:
Strong admin controls and powerful automation capabilities in concert (no pun intended) with tools like UrbanCoder for deploying releases.
Good universal work item reference system. Everything can always be found using these, unlike other systems that will use different (i.e. non-universal) references for different things, confusingly enough.
Great for managing work-streams and giving your client/business stake-holders views of your progress via easily managed browser-accessible dashboards.
Relatively easy to manage the forked development of existing stable releases by different teams, or even within the same team if need be for experimental bifurcated development.
Everyone in the SDLC has a role in RTC. Truly everyone. This makes access really nice to control.
The admin controls are powerful but there is a steep learning curve and you WILL need support from IBM to help you there. It's just too damn powerful to manage easily at the start if you're new to it as an admin.
The concept of the SDLC in RTC is very good and plainly obvious but if you're bringing this tool into an existing organization, your devs, testers, etc. will NOT accept it readily. You MUST ensure that they have adequate time to be trained with it, have sessions to just experiment and be able to ask questions, and offer unlimited retraining sessions. Seriously. Make the RTC admins own that, because ultimately that will save YOU time and frustration as an admin as people will start learning the RTC method and become less and less likely to cause huge alarms and panics in the last hours before a deployment is scheduled.
Ensure you have plenty of time allocated for training, more training, and retraining. Forcing RTC on users with no time to learn to use it properly is a recipe for disaster.
Managing the whole SDLC, from planning, development, testing, and release into the production environment.
It manages code-bases across all projects, year after year, compartmentalizing development streams readily in projects with ease.