It is always a sensitive point when an artist should stop touring. As a living legend to so many fans, the desire and enjoyment to carry on will always there. We all age though and each passing year puts more demands on our bodies. A lot of artists are past their best but carry on, this can do a disservice to their legacy - you don't want fans to remember you for your last few concerts when you simply were past it. There always going to be fans that want to see them regardless, and its very difficult sometimes to be objective ourselves as passionate fans. The reality is that MK is going to be 67 this year.
I have been fortunate enough to see him a number of times over the years and it was an amazing experience. The 2005 shows in Johannesburg were probably the 2 best from a musical point of view I have been to.
MK is really struggling on the vocal side in the last few tours. The first few shows are fine, but then his voice takes serious strain after that. You can listen to recordings from early on in a tour, or after a break and then a few shows later and you will hear the difference. Others have commented he doesn't play the same guitar licks and parts on a lot of his songs as he used to. I am no guitar expert so cannot comment, and I personally think his guitar, backing band sound as good as ever, but there will be a time as well when perhaps the guitar won't sound as good as it always did. These comments are not meant to be critical at MK as a musician we all love him for, its simply to recognise that he is ageing like we all are. Whether you are a professional sportsmen, performer or musician, it is just nature that you cannot keep on performing at the same level year after year indefinitely.
If MK just does decide to just do a few charity shows here and there, I think it is a great move. It will keep his vocals in shape, allow him to put his full passion into it and removes the rigours of the longer tours with the associated physical and mental attrition. The tours also take up a lot of time and probably remove studio time. I would personally like it if he takes this approach as it will still provide live concerts but also allow him to produce another few albums in quicker turn around time.