Frequently bypass 4+♦
which can be checked or not. I presume (I don't think this entry was on convention cards when I stopped playing almost 20 years ago) this pertains to auctions where there is a 1♣ opening and opener's partner either does or does not show his 4-card diamond suit. This box is not checked on GIB's convention card, so I would expect GIB to bid "up the line" with 4D and 4M, and bid 1♦ in some of these other cases:
I haven't been able to find a single hand where GIB bid 1♦ over partner's 1♣ opening holding only four diamonds. Should that box be checked, or does it mean something else?
When GIB does bid 1♦, the description says "4+D" but he only seems to do it when he has more than 4.