I totally agree. However, knowing the particular advantages of one approach vs another takes time to learn and understand. All well beyond the experience level of a young engineer, On the other hand, I quess that was why the question was asked in the first place.
Having some recent experience in this, namely 2D Kalman image filtering for real time fluoroscopy, I would offer the following advice. Start by tracking retro reflectors on the humans shoes, then track the shoes with/without the retros. Then graduate to the larger problem. If you have Matlab with Simulink USE IT. It will save you a absolutely huge amount of time.