Simulating a postflop scenario. I have a question about +EV / -EV decision on the turn.

Hero: 10h10c
Villain: Unknown

Flop: 5c6s8c

Villain: checks
Hero: I Bet 25% Pot (+13.8 EV (50.1%) or alternatively could have Bet 80% Pot (+12.9 EV 0.9%) or checked (13.8 EV 49.1%)

Turn: 4d

Villain: checks
Hero: I elect to bet 80% pot (16.5% EV) other options include: All In 247% Pot (12.4% EV 0.02%) Check (18.7% EV 25.6%) or finally the preferred option of: bet 25% Pot (18.7% EV 74%)

GTO trainer says blunder/mistake with my 80% bet. I have an over pair. I typically take a Small bet 25% Pot ——> Big Bet 80% Pot line in this situation.

why is this such a mistake in the eyes of the trainer? any insight would be greatly appreciated. i’m totally confused by this recommendation. Am i missing something? Do i want Villian to call 25% bet with flush and straight draws out there that scare me?