More hexcrawl confusion from TSR can be found in I5 The Lost Tomb of Martek.
Wilderness hexes are 2 miles.
The module rules: 12" movement rate = 1 hex per hour. Only 10 hours of movement per day.
Unpacking that, you get 10 hexes of movement per day, which is 20 miles.
B/X rules that a 12" movement rate should yield 24 miles per day, but desert travel is only 2/3 of that, yielding a 16 mile travel day.
Random encounters, in I5, are checked every four hours, which sounds like 6 checks per day. That is significantly more frequent than my reading of the rules. We're I play testing this module, I would have asked Hickman if this was necessary.
Now, Hickman's module rules are not far off from the canonical rules, but why bother writing new rules at all? Standardizing wilderness rules makes it far easier for experienced GMs to use the work. I feel the hobby is still groping toward this kind of standardization.
Does this mean every module must follow the standard rules? Of course not. However, rule deviations should be used only when there is a compelling design motivation to do so.