The Buddhist philosophical structure is circular, like spokes of a wheel, whereas the yoga format is fractal in form, like the growth of a tree. Maybe this accounts for differences in philosophical format.
I also think there are irreconcilable differences regarding God and self, but mostly because Buddhism isn't particularly concerned with self-theory, and the no-self, non-self stuff is contextual in meaning; not absolute like an answer.
Other than that, it's the same basic 8 path. The Buddhist one probably culminates in equanimity rather than bliss --- but that's from someone who knows nothing about yoga, but has heard about Patanjali, and definitely and gives him the benefit of the doubt. I imagine it's a lot like Buddhism. There is a 'true message' in there somewhere, but it's not very well understood.
