[Pharo-project] Is there something wrong in debugging in the Morphic thread?

Unfortunately, this is an issue which I cant easily reproduce, at least not without a third party tool (1525). Now I would like the general opinion/experience of debugging Morphic code especially in threads. Usually an exception raised from within Morphic code pops up a debugger as usual. However, from time to time, or for more complicated stuff, the situation runs out of hand and tons of debugger pop up everywhere because the same faulty gets obviously executed again and again. Now can somebody with some Morphic knowledge explain how this is supposed to work and how to deal with such issues? -- Simon