Did you even bother to read the
article which had
Federer's opinions on this topic. His complaint was not that IW and M are too close. His complaint
is that about 5 days of his time (if he is successful at IW) and up to 14 days (if unsuccessful at IW)
are getting wasted as he (and of course other players) had to wait for M to begin after getting
eliminated at IW.
It is really a good decision to skip M for Fed. You skip only one ATP 1000 event, but you
get two weeks off. On the other hand, if he skips MC for example, he again misses only
one ATP 1000, but gets only one week off.
Even the winner of IW has to wait for 5 days to begin playing in M due to draw size
being 96 and the first round bye.