Thanks for posting the video!
As for portal expectations... I think it's all there in your own words. You expressed concerns about Merk making poor reads and not seeing the whole field (which our offense arguably doesn't require), but he's had 2 years in the program, learning this offense every day. GMac has had 3 very intense months of learning it. Neither has been getting starter reps (...for some reason, that I've now forgotten) in Spring practice.
The point being: are they not going to be far, far ahead of anyone they can bring in from the portal?
Now, if the challenges for Merk and GMac were arm strength--sure, we might be looking to gain a starter from the portal.
But that's not the case. What we need from the portal is someone who can become a viable third-string QB by August, and maybe--maybe--compete against GMac for the backup role. But Heupel wanted GMac out of that entire class of QBs, so we know he sees in that kid someone capable of executing his offense to a national championship.
Heupel just couldn't see that the timeline for development was going to jump ahead 2 years overnight.