Ur.Also, off-topic, but what's your +-centers buffer?
I have two reasons for thinking about reorientation. First, to save moves. It might not always be worthwhile but if the default orientation is bad, say <6 solved centres, and the cube can be reoriented to solve 16, that's 5 comms saved in exchange for 4 moves to switch centres.
Secondly and for me more importantly, to shorten memo. Those extra 10 targets take more time to memo than the few seconds to check orientation. Plus on 4x4, I use audio for centres if there are <=16 targets, but am pushing my limits with nore than that so on 5x5 I use visual. If I could reorient 5x5 to have <=16 targets for either X or T-centres then I would use audio on that scramble.
However, my gut feel based on experience is that the 7-8 for 4x4 doesn't extrapolate to 14-16 on 5x5 like this, which is why I asked the question. I don't recall ever getting a scramble that good. My suspicion is that a good orientation for T-centres would rarely be as good for X-centres and vice-versa, so the most typical cases would be 11-12 centres solved.