Chuck
Yes its a valid point and indicates something not quite right somewhere.
However, consider the following (its not in the AIB report - just surmising).
Guy turns up at aircraft, sees the tech log, and guestimates there is about 30 USG residual fuel. This would be about 1/4 tanks. No point making an inspection, you can't see it when its that low, apparently (from the AIB report). However, he asks the refueller to put in his route fuel, 30USG each side, which would bring it up to about 3/4 tanks each side. Maybe a visual inspection will show fuel, but no telling how much - besides the refueller has just put in enough, hasn't he? Jump in the aircraft, throw the switches, look at the gauges, one says 3/4 - yep, OK. The other says full - "oh, there must have been more left over in that tank than I thought!"
How about the tanks on the return? Nothing said here in the AIB report. However, if an hours fuel had been used, the gauges would show 3/4 and 1/2 - plenty for the return flight of one hour. Plus, no point in a visual check, you can't see the fuel that low down, it seems.
After an hour's flight on the return, the tanks would be showing about 1/2 an 1/4.
From the AIB report, when arriving over Shoreham and performing his checks: "As he did so he noted that the fuel gauges indicated 'half full' for the left wing tanks and a 'quarter full' for the right tanks. Sounds about right doesn't it?
Then the engines quit, presumably because the tanks were empty! Now, the gauges are supposed to be accurate when empty - but they were reading 1/2 and 1/4 full - hey that's WAY out.
Now, if the aircraft landed without fuel there are two reasons, not enough fuel uplifted, or fuel leak en-route. Take a look at the AIB report. Does it even mention this second possibility? Does it even try to investigate this possibility? No! The only comment is "The left wing, outboard of the engine, was almost detached. The right wing was still attached, but the inboard section of the right wing fuel tank had been ruptured by an impact with a low concrete wall. There was little evidence of fuel at the site; some fuel had drained from the right wing down the wall, destroying a small amount of vegetation beneath. There was no evidence of fuel from the left wing."
A fuel leak is not even contemplated, researched or denied. There is no mention that a fuel gauge reading 1/2 or 1/4 for an empty tank is outside the tolerance error on the gauges.
No, either the pilot is lying, or he was genuinely caught out by gross errors in the gauges or there is more to this which has not been properly investigated.