Confusion on the wiki tutorial to "Improve the Pokédex AREA functionality" #520
Description
In the wiki tutorial to Improve the Pokédex AREA functionality, it states that "Tentacool appears in 3 maps, 10 slots each, for a grand total of 30 individual encounter slots.". However, ignoring the Super Rod encounters, Routes 19 & 20 are coded as a single table of 10 encounters, so wouldn't that leave Red/Blue at only 20 Tentacool encounters, or is the logic still 30 as that set of 10 is pointed to twice? Beyond that, Yellow split those two routes separately in addition to more Tentacool encounters in Seafoam Islands, bringing the Tentacool encounter count to 40. The fix listed does not seem to be present in vanilla Yellow, so what did Yellow do different that prevents the mentioned bug from happening and why isn't the fix to use Yellow's vanilla fix? (Or is the mentioned bug actually present in vanilla Yellow?)
Please ask for clarification if something I said doesn't make sense; I was struggling to structure my sentences properly.