Not a lot of information on there CW, but from the description of the rafters/joists it sounds like an older building.

I'd ask for a description of the state of the brickwork, if only to firm-up my opinion, because it could explain the use of resin-fixed bolts. The only thing I'd question is why the SE has stipulated individual hangers instead of resin-fixing the bolts holding a wall plate along the party and gable walls and hanging the joists off that off joist hangers.

Just because the method's 'different' doesn't make it odd. But then it was posted on the GBF and they do have a tendency to turn things over and do a forensic inspection for hidden markings and then discuss the possibility of hidden consequences for the future existence of the human race.

The SE sounds like a bit of a dickhead. God knows where he's coming from on this one.

Trimming around the chimney breast means you can fix the wall plate to the party wall/gable end (whichever wall the chimney breast is on AND around the chimney breast, fixing it together at the corners by either mitering, screwing through and reinforcing with brackets, or just fixing at the corners with brackets, putting fixings into the SIDES of the chimney breast as well. That isn't going to go anywhere!

The idea that individual joist hangers are somehow better than a (load-spreading) wall plate seems a tad eccentric, because you can resin-fix the wall plate bolts at the same centres and get a far superior location for the joist hangers.

What do you think Jerry?

Trouble then is, the bow will put the joist hangers out of true.

I've fitted wall plates in stone barns where you'd be hard-pushed to find a straight line. We put the upper storeys in using 1/2" (it was that long ago) threaded rod epoxy'd into the masonry, and packing to give a tight fix. The nuts and washers were counter-bored flush and a 2" board (slotted to take the joists) glued and screwed (again, counter-bored and plugged) to the face. It was all oak so looked of a piece when done. The gaps where the first plate didn't meet the wall were just lime mortared to match the existing.

The reason for using epoxy is to avoid the pressure of something like a rawlbolt splitting the stone/brickwork. The pressure created by them is incredible. I'd made a new iron ladder to fit into the tower of Broncroft Castle (privately owned, it's down the Corvedale in Shropshire) and as I tightened the second rawlbolt a hairline crack appeared in the bloody great slab of sandstone. I backed that off pretty smartish.

Maybe the SE does see something no one can see, he is on site after all, so perhaps a closer questioning of his reasoning might be in order. If his only concern is getting around the chimney breast then he really shouldn't be doing this kind of work until he's got his knees a bit browner.