"A win for Celtic Swing would have been by far our worse result," the firm's chief odds compiler, Mike Bellamy, said.
"He was 7-2 favourite after his win in the Racing Post Trophy last year and was well laid at 7-2, 3-1 and 11-4 into 2-1 at the time of the 2,000 Guineas.
"Pennekamp would not be a bad result, he has always been a reasonably short price. He was 10-1 after he won the Dewhurst last year and 6-1 at the start of the turf season.
"But betting on the Derby only really hots up after the Guineas and by then, with Celtic Swing doubtul, he was 4-5 which isn't really a working- man's price."
Nor would wins for Spectrum or Munwar be a big triumph for ante-post punters. "They have always been prominent in the list and were only 20- 1 and 25-1 at the start of the season when it was 20-1 bar two," Bellamy said.
Of the likely runners, Sebastian is William Hill's biggest loser. "People latched on to him after he won at Salisbury and he was backed down from 25-1 to 16-1," Bellamy said. "Then he was suddenly punted down to 10-1 on 26 May and has been steadily supported again since."
Bellamy's advice - to those who believe in taking advice from bookmakers - is to back the French 2,000 Guineas winner, Vettori, whom he says represents value at around 20-1.