I have been using ClearQuest since around 1997, and ClearCase for longer. I’ve worked on schemas in many banks and other large companies, around the world. I co-authored the tools on this site. I’ve delivered training at various levels around the world. I’m certainly not the last word on ClearQuest, but I think I know it pretty well.
To be frank I’m not sure how ClearQuest came to have such a large installed base. The decision makers tend to be IT managers, not process or release engineers, and heaven forfend that any one that’s actually going to use it should have any input in to the decision. These IT managers hear the right words, “full audit trail”, “configurable process”, and most importantly “integrates with ClearCase”. They hear: web client, native client, Rich Client Platform-based client, and they don’t think - “Jeez, how are we going to support and maintain all those clients and deal with their myriad differences and quirks”, they think, “ooh, 3 clients, that should cover all the bases”. No one got fired for buying Microsoft, and people rarely get fired for buying IBM, so they go with the herd and blithely hand over several hundred grand.
A few years ago I gave a ClearQuest admin training course to a financial exchange. I was explaining some quirks in the Designer that they were struggling with, and they looked at me and said “why did we buy this?”. I didn’t even sell it to them! I thought: you fucking idiots, you’re asking me why you bought this? You’ve just coughed up a quarter of a million pounds for ClearQuest licenses and you haven’t tested that it works! Where is the due diligence? And I find this pretty typical. ClearQuest is chosen using a stock list of “requirements” - usability and maintainability do not figure in them, or the managers are too apathetic and credulous to test it themselves.
