They do use the 14mm a lot nowadays (Para 2, Manix 2, Stretch 2 etc) so I definitely think it's a possibility. However, if I were going to guess, I'd say a 13mm hole is more appropriate based on the smaller size. They used a 13mm hole on the Superleaf badespite the robust design, and it's much bigger. But 14mm is certainly possible. If I were designing it, I'd probably go 13mm--I think that's the size that is most comfortable. At 14mm, too much of my thumb goes all the way through. However, when wearing gloves it is a great advantage.
PS-just checked out one of Mr. Blonde's prototype pics on google images--it's hard to tell the size, it could be 14mm, but my guess is still 13