Sounds like you had quite an adventure Paul. I am well aware of the confusing road layout at Raglan - especially for those coming up from the south visiting the Castle before heading west to Abergavenny. I would probably have warned of this confusing road configuration in my response to your original posting. Click the link and we can see the road network at Raglan:> https://email@example.com,-2.843875,1402m/data=!3m1!1e3
So, coming up from the south (Bath & the Severn Bridge) on the A449 you would swing west at Raglan interchange onto the A40 only to loop back at the first roundabout and then turn left into the Castle. So far so good - hopefully. Now comes the confusing bit - you come out of the Castle driveway and are forced to turn left (east) and if you do not take the next left and then loop right and take the westbound A40 expressway towards Abergavenny - you would end up either going NE towards Monmouth on the A40 or south again on the A449. Try and follow this on street view to try and see how it should have been done.
Most of the journey up through mid Wales to north Wales would be a simple matter of following the A470 - which is well signposted. Now, for some strange reason you ended up going way off route via some backroad through Ysbytty Ifan. I can only think that you might have been taking ‘orders’ from some satnav or Google? You just can’t trust these things as very often they just connect 2 places with the shortest route - even if it is an unsuitable narrow mountain road. Had you stayed on the A470 just following the road signs to the next place, I think you would have been OK. The lady you met in a remote village must have been very surprised to have some lost Americans knocking on the door.
It is quite a long drive from Bath to Conwy and I think you might well agree that it might have been well worth while to at least spend 1 night in the middle of Wales. It is regrettable, in my opinion, that few Americans venture into this part of Wales. The most prevalent foreigners appear to be the Dutch as I often see them driving about with their NL number plates.
The big question is - was I right to suggest driving the scenic way through the middle of Wales or would you have been better off driving on motorways (like interstates) through the English midlands via Birmingham?