Underweight and Undertrained

I have tried the strategy of arriving at the start line overweight and undertrained and it has certain advantages but non that matter once the race starts. Hauling a flabby underpowered carcass up countless mountains does little to uncover the merit of this as a sound strategy. So pot-bellied, lethargic wannabe athletes where on earth does this saying come from? It's the antithesis of "don't arrive at the start line overtrained and underweight."
You will be pleased to know that I haven't fallen into either one of those traps. I shall arrive underweight and undertrained. Work and family commitments have assured I didn't overtrain. In previous years I put in as many as 25 hours a week in training. 2011 was the year I trained the hardest and the year I failed miserably at the Freedom Challenge, pulling out toward the end of day 2. This year I have focused on shedding surplus blubber, getting reasonably fit and planning to arrive at the start line without any recently healed or irritating physical niggles.
According to Strava, in the last month I have ridden only 11 times covering 556 km's in 28 hours 34 mins. These read like the riding stats of a typical weekend warrior not someone looking to charge down the trail to the adulation of their many fans. Fortunately there are no fans to disappoint and the charging will be a relative term. I am looking to race myself. Simply trying to see if I can better my 2012 time of 71 hours to Rhodes. I need to stay focused on that one goal and ignore the antics and surge of the riders around me. Clock is ticking slowly. Enough already, I just want to ride my bike down the trail!