Route 3 end HP from the top Red runs:
13/41
17/39
7/40
22/39
1/40
15/40
17/41
25/39
28/38
12/40
9/40
25/41
22/41
5/38
10/40
16/38

Average: 16.2

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Mt. Moon

Magnemite: 3 dmg with 11-15 DV, 4 dmg with 0-10 DV
Voltorb: 3 dmg (5 crit) with 7-15 DV, 4 dmg (6 crit) with 0-6 DV
Caterpie: Always 3 dmg
Paras: 4-5 dmg

Nidoran to Nidorino is +4 or +5 HP
- Red bar at L16 (Nidorino): 0-9 HP (0-10 if 8+ DV HP)
Nidorino to Nidoking is +6 or +7 HP
- Red bar at L16 (Nidoking): 0-11 HP (0-10 if 0 DV HP)

Full Mt. Moon red bar (almost impossible) saves ~22.5 seconds (3 on Nerd, 4 on BC, 5 on Paras encounter, 3.5 on Rocket, 7 on Nerd)