First, the hand that's the example of what I'm asking about regarding blockers:

HJ villain is extremely loose-passive: 91/17 with low aggression over a medium-sized sample by Ignition standards.

Also, Hero was in a probably -EV "whenever possible, cheaply see a flop with any suited ace" phase. I've tightened up preflop since.

Dealt to Hero: 9 7 2 A

HERO Calls $0.25, HJ Raises To $0.50, CO Folds, BTN Calls $0.50, SB Calls $0.40, BB Calls $0.25, HERO Calls $0.25

Hero SPR on Flop: [3.86 effective]
Flop ($2.50): 9 7 A
SB Checks, BB Checks, HERO Bets $1.25 (Rem. Stack: 44.22), HJ Raises To $6.25 (Rem. Stack: 17.16), BTN Folds, SB Folds, BB Folds, HERO Calls $5 (Rem. Stack: 39.22)

Turn ($15.00): 9 7 A Q
HERO Checks, HJ Bets $15 (Rem. Stack: 2.16), HERO Raises To $39.22 (allin), HJ Calls $2.16 (allin)

For all practical purposes, can we always put HJ on a nutted combo draw at worst and feel confident that we're GII good on the turn? Are sets so rare here due to our "three pair" that we can't really give sets any significant weight in assigning HJ a range?

(I guess we're also in trouble against AQ9 hands but meh. Not worried about that; the turn Q really doesn't do much except sap most flop draws' equity with only one more card left to come.)

River and HJ's holding below.

Open fold pre, don't donk the flop (especially not half pot). Fold to the flop raise unless you think villain is really splashing around in this five-way pot -- anything resembling a strong range has you in bad shape, even after card removal.