At the more crowded times of the year, the day-by-day recommendation sites like TP and EasyWDW typically recommend avoiding EMHs. The "Unofficial Guide" is a more generic book that tries to capture everything in one place but is less concerned with the day-by-day, hour-by-hour touring like the other sites. TP and EWDW suggest avoiding EMH (especially on crowded days) because they know that people's best intentions are often foiled by a late bus, by a longer wait for a cup of coffee, or just by not getting out of bed as early as you think you will. Both sites agree that EMHs are great if you make the RD of the EMHs. But many people saunter in to the park only 15-20 minutes early due to delays and miss the first and most important 40 minutes of EMHs. And lots of other people do the same thing, thinking that it would be great to go to the park that has the extended hours. So a day that might otherwise be a "6" turns in to an "8" because of all the people enthused about going to the park with the longer hours. If you make the RD of the EMH, that is great. You really get a huge benefit. But by 10:30, the park is more crowded than on other days of the week. So it is a trade-off. Do you reap the benefits of the first hour in exchange for a more crowded 12 additional hours, or do you skip the beneficial first hour and head somewhere else? But here is the kicker. TP and EWDW are predicting that the average guest will miss out on most of the EMH, arrive later than they thought they would, and get the worst of both worlds. No EMH benefit and a larger crowd the rest of the day. The Unofficial Guide is giving advice to go to the EMH, and is expecting that the reader will take that advice in spades. The other sites are realistically assuming that not everyone will be so ambitious at 6:30 in the morning.