Not an answer, but just a remark: It is no longer mandatory that WEIL pushes the verb to the end. Like with any other reform, some Germans find this disgusting and there is some controversy, for example, this text is funny:
Another, not completely off-topic, remark: when speaking German with natives (or at least when trying...) I have understood why there must be inversion for some particles and why not for others. It helps the listener distinguish the particle itself (and so the meaning of the whole sentence).
For instance, you may easily confuse denn and wenn when hearing a person's voice in the middle of the street. But the inversion helps distinguish between them:
Anne geht nicht spazieren, denn sie ist krank.
Anne geht nicht spazieren, wenn sie krank ist.
If "wenn sie ist krank" were right, you would easily confuse both sentences.
(It is an off-topic remark, but I think it is interesting and, up to some degree, related)
I don't know why they did that reform for the use of weil. For me, it sounds horrible without inversion...