(2)...(c) the WCT when viewed as VT looks like it's coming from where the scar is known to be, collectively make VT much more likely.

(1) More likely VT.
The algorithms are more helpful when you don't have the sinus ECG to compare with. In this case, you do. Knowing that (a) the patient has nontrivial scar burden, (b) the QRSs, especially the intrinsicoid, look so much different between WCT and sinus, and...

Yes. Simpler to achieve, with comparable outcomes.

I'd also want to try to isolate which part of the lead is affected and see if we can pace unipolar (or "integrated bipolar"). I'd confirm that the conducted QRS is indeed wide. If those steps don't help then I'd start looking at the patient overall to determine candidacy for surgery.

2. , talk to them about possible extraction + reimplantation, likely with LBBB lead. I'd want to confirm in person that it's still going on.

Not necessarily in that order.

1. I'd want to know if it abruptly got that way or if it has trended in that direction for a long time. I'd want to know what "very high"means. I'd consider that fracture is a possible diagnosis and want them in the office to look for noise with pocket manipulation...

Not calculus: subtraction...

Whoa. This just took me by surprise and brought tears to my eyes.

Got it. Now I am interested as well. I feel better knowing that I am not missing something obvious! (Maybe both of us are?🤷‍♀️)

So why would enabling BiV pacing and reprogramming the LV polarity make the unipolar ring impedance drop? (Unless the impedance numbers prior to reprogramming the device were somehow spurious or wrong?)

Was surgery done? Something affected just the ring button.

I think AVNRT

I love it! What product is this?

Looks like atrial flutter