Actually, this could turn out to be a stroke of genius. Make the announcement on the Labor Day Weekend, and release a statement to the effect that political campaigns had been starting earlier and earlier, and that he chose not to do so to try to restore some sanity to the election process. This gives him the "high ground" and makes his opponents look like over-eager amateurs.
At the rate things have been going, I was concerned I would be getting my 2016 election bumper stickers in February...