Currently I've got some page titles from an old system that outputs the entire category breadcrumb as part of the title when a category listing is viewed.
So you end up with a title like so...
Category currently being viewed | Category Above currently viewed | Category above that category | Website/Company Title
The Website/Company Title
part appears on every page of the site however the other things appear as needed. You end up with a lot of very long titles like this especially as people drill down through category listings into subcategories.
You also end up with a lot of duplicate content in titles because you could have a page that is something like Category 1 | Website/Company Title
Category 2 | Category 1 | Website/Company Title
Category 3 | Category 2 | Category 1 | Website/Company Title
These titles get even worse when you add in pages to the listings like...
Category 2 | Category 1 | Website/Company Title - Page 1
Category 2 | Category 1 | Website/Company Title - Page 2
Category 2 | Category 1 | Website/Company Title - Page 3
and so on.
A lot of the conventional wisdom from sites like Moz say the best idea is to keep your titles around 60 characters if you want the whole thing to show up.
In this case the most important part of the title for SEO at any given time is first. My concern though is that SEO heavy terms are appearing so many times over and over again that it starts to appear as spam.
What I'm told is the original argument for this was that it helped with SEO at one point in time because you got more terms in the title which might be relevant to a given category listing. Also that it may help Google understand the structure and position of content in your site in relation to other things and terms
This seems 1: to not apply to the title tag and just breadcrumbs (and other content) on the page, and 2: seems to go against other ideas of good titling conventions.
As sites balloon in size, and Google is getting better at determining good content from bad it seems like these titles with heavy redundancy can't be helping and it would be better to move to a format like...
Current Category Title | Website/Company Title
I do not know for sure though and couldn't find anything closer to this specific problem as I googled around so I wanted to get some other opinions.