MakeItSmooth, we are where we are. You already made your point about reskimming over old walls is a bad idea.
Yes, and you stayed silent and took a day to admit that you already knew that some of it was blown.
And no previously the wall wasn't sticking out like that however the plaster was blown so they removed that section and added bonding. I thikn they put too much bonding AND also too much multi finish. You can see to the left of the socket, the multifinsh layer is very thick (more than 10mm whereas on the right hand side is about 5mm).
Then why are you wondering what happened in the other corners of the room?
Quite clearly, there is a pattern emerging, is there not?
we were expecting smooth walls with no noticeable waves/bumps however we found that some walls had some waves especially near corners and next to doors and windows.
We noticed that quite a few corners were sticking out a bit and as a result had lost the detail in the picture rails and skirting boards. We think they put too much plaster in these corners. We asked the main plasterer and he's blaming the old walls but we are not convinced.
We also noticed that in the gaps between walls and architraves of doors and windows, the plastering is quite rough and wavy. Not too worried about the rough part as that can be sanded down but I'm not sure if you can get rid of the waves/bumps by sanding. We asked the plasterer about the waves and he said because of the small gaps, they couldn't get their trowels in to make them smooth like other walls. I measured these gaps and they are anywhere from 8cm to about 11cm. They might not be able to get the standard plastering trowel in there but I thought they could use something smaller to make it smoother. Or more skilled plasterers would have somehow done a better job. Are we being unreasonable?
No lack of space to use a trowel properly, around the bottom of the wall by that skirting board, so the lame excuse about the other corners having dodgy plaster due to not enough room to use the trowel does not stack up. Maybe the old plaster was just as bad, and only you as the houseowner know what it looked like before. Had it been badly reskimmed a few times, over the years?
In any case, the surface finish of the plastering around that skirting board is clearly not to a professional standard.
Please don't think I'm trying to make you feel bad - I'm just giving you my honest opinion. Even a highly-skilled plasterer would tend to avoid patching and reskimming over 100yr old plaster, because it is not the right way of doing it and is fraught with potential problems.
When you add an already dodgy scenario to a plasterer with questionable skills, I'm actually amazed you got away with it as lightly as you have. I don't like to disrespectfully accuse anyone of having questionable skills, but I can arrive at no other conclusion, looking at the state of that 'workmanship'.
However, you need to accept a big chunk of the responsibility for this situation. In trying to patch ancient plaster, you were setting the plasterer up for a fall, and someone was willing to take a punt at earning from it.