I got an KF*G upgrade 2 years in a row. The year before last I did well over 150,000 but I don't credit my miles on SQ because of the poor burn rate. As they allow you to keep your other FFP in your profile, they would have been able to track the number of flights and miles I could have obtained had I chosen to credit to KF.

Now fast forward to last year and many flights are earning 50% on SQ and nothing on my other FFP. So I am becoming more of a KF by default, reaching about 47000 miles (still travelling in excess of 150,000). This time one return in paying biz and accrued some PPS credit. Received a Silver card upon expiration of my gold card and about a week later, an automated email telling me that I had been upgraded to Gold.

So that's two years in a row.

I think SQ is using some data analytics to assess your travelling patterns and try to lock you in. To me the only advantage is access to the lounge when flying MI and the 25% when I have requalified on LH and TG.