Curious to hear what Teneuss says. I forget where I heard this, but not playing hands just to avoid tough spots < learning to play these tough spots better. With that said, I still feel like 78c is too loose for me without a solid read. I think Teneuss probably had one. I think 89s is the very bottom of my range and to be honest I probably fold that some of the time too, T9s is a call for me. My games are a lot different than his with less 3-betting/4-betting so I guess I do tend to flat a slightly stronger range in general. With the aggressive dynamic of his games this might be a call, I'd like to hear him explain it too.

What is the smallest SPR you would take to the streets here to a normal size xbet? It seems like this is borderline to me and some would say is just a 5b or fold decision.

As far as preflop, like I alredy said I wasn't sure about the decision ingame at all.
It looks like I have around 33% equity against his range, and we need 31% equity to call.
So purely equity wise the call is fine, but we are obviously out of position and we will not be realizing the close to 100% of our equity, so it seems like you are correct to fold here.
As far as suited connectors go, the equity difference between 78s and JTs is fairly small, but R will increase so I think defending 9Ts+ is fine.

I was interested in this spot on my own, and by playing every AhXh this way(checking flop, to call turn and raise every blank river with AhXo and AhXh you're going to have 7 combos, gave him every Ah2h - AhJh, and then AhJx (AhJd, AhJs,AhJc) 3 combos and AhTx 3 combos(6 combos of bluffs). So given villain checks to us on the river and we fire, we're going to have even more value combos assuming we're betting KQ+ (9 combos) or better, making it total 16 value combos, and only 7 bluff combos. Assuming we don't call 3bets wider than ATo preflop, if we do, then we're only going to be more bluff heavy on the river. Hope that helped, obviously Teunuss can tell us more about it if I'm incorrect.

Thanks!

1. I am certainly checking a good percentage of the stronger nutflushdraws which have decent showdownvalue already, that don't have as many incentives to bet flop as a other flushdraws. AhJx does seem like a hand that can surely start betting flop already though.
   Other things are already mentioned by Everize!

2. You are correct, I thought it would make sense to call most of my Ahxh hands but against this sizing we certainly don't have to be calling that wide, we are easily calling over half of the time if we leave out all the AJhh-A2hh (exception of A5hh ofc), so certainly a mistake by me.

I don't think it's necessarily the case that we merge, I picked this sizing because of our range advantage in this spot, and therefore by betting small we can bet closer to fullrange and do a lot of protection betting.
The difference in EV for my range between the two sizings seems fairly small, the 'perfect' betsizing is certainly larger than what I picked ingame. But you could argue that a strategy of smaller flopcbet is easier to play and we will certainly not make as many mistakes so that could make up for the fact that we give up a small bit of ev.

the AK hand, we are probably shoving around 9 combo's of value (mainly AK obv). So the best combo's to add will be AQ combo's without hearts.

I think I agree with you, ingame I was also debating whether to pick a smaller sizing or not. I don't think we really have to worry about him having a lot of AK combo's that potcontroll, because those combo's have a big incentive to shove turn. Like I said we don't even have that many bluffs, and have all the AQ/AJ combo's that are indeed interested in getting some thin value (especially AJ is somewhat thin), so it certainly makes sense for my valuerange to bet smaller, so I totally agree with you.

So, I wait "Like" ;)