The link you are reading may be old and refer to some of the harsher insulins used that lower blood sugar rapidly upon injection. (N, Vetsulin/Caninsulin, Lente) The newer insulins (Lantus, Levemir, PZI) give a more level curve and for most cats don't need timed feedings to work.
Of course if you're using one of the faster ones, then it may well be a good idea to follow those instructions.