A criticism leveled at the pilots at the time was that they had no experience with towed ships, which is fair comment, and which does come over strongly in the Petewidders feature article. A little ship with the nicety of control of her own helm and engine bears not the slightest comparison with the very loose control possible over a deep tow smelling the bottom in a narrow channel in a tubulent tideway with tugs further disadvantaged by long scope single hawsers ^{(note 12)}. (There's a plethora of sites on the Web addressing the problem of ship interaction in narrow channels). It was also fairly stated that the pilots had no experience with ships anything like 22 feet draft, and we can sympathise with Capt Hewitt's reluctance to accept pilot's advice on the question of the available depth. After all, that as late as February 2000 Richard Jones saw the need to physically measure the depth over Cheese Rock doesn't say too much for his familiy's prior knowledge of that depth. Indeed his father, Emrys Jones, told me that in his day even on a big spring tide he regarded 17' 6" through the Swellies as "the absolute maximum", on the other hand his need to berth at Caernarvon on the last of the flood meant he regularly 'powered' these little ships through the Swellies against the flood about an hour before 'The Slack', when figures show that on such a tide the least depth (Cheese Rock) would be about 19' 8".

But in solution to the problem there was a clear obsession with the highest tides of the year - the most dangerous tides of all. We've seen that at the western end of the Swellies (Pwllfanog) on the highest tide of the year the tidal range is 20.3 feet. West of Britannia Bridge the chart states the Rise at neaps is 14.5 feet, which minus half the springs Rise (9.5 feet) is 5 feet above MTL, giving us a Neaps Range of 10 feet, and 82% of this ^{(page 12)} gives us 8.2 feet as the Range on the lowest tide of the year. The duration of the Rise averages 336 minutes. When the pilot wanted to pass over the rock (around 0858 = L.pool -2.20) the interval before HW Pwllfanog was 71 minutes. Thus Ht. above MTL = ...................... sin[90 ~ ( ⁷¹/₃₃₆ x 180)] x ^Range/_{2 ...} = ... 0.788 x ^Range/₂ . ... Thus around L.pool -2.20 the height of the tide above MTL at Britannia Bridge would be..... 0.788 x ^20.3/₂ = 8.0 ft. on the highest tide of the year, and 0.788 x ^8.2/₂ = 3.23 ft. on the lowest.

Thus at the critical time the difference between the highest and lowest tides of the year was only 57 inches. (It's by no means unusual for the barometer to vary between 980 and 1030 mb, which alone will vary the depth by 20 inches, yet this played no part in the thinking). This, together with the foot clearance the ship had at 0858 that morning suggests that if instead of the 4 ft. sounding over Cheese Rock the least depth in the channel shown on the chart was 7 feet, the ship might even have made the transit at neaps, decidedly so with a low barometer and southerly wind, and in any case well away from the severe streams and brief period of 'Slack' associated with the highest tides. Studying the chart shows the bottom in Cribbin Gutter to be highly irregular, but there were only three or four small rocky upstands which needed to be flattened and the spoil removed (albeit involving controlled explosions) and the situation would have been transformed. It would then have been possible for the ship to have made the transit in the much more relaxed circumstances of a far more forgiving middle-height tide. But permission to conduct such an operation invoving the use of explosives in the vicinity of the footings of Britannia Bridge - the only rail link to the Holyhead Irish Ferry - was quite unlikely to be forthcoming. Instead what was required of Capt Hewitt was very far removed from what we used to call 'the ordinary practice of seamen', but which had much more the character of a stunt. We cannot be at all surprised that it ended in disaster.