Great topic.... Titles.
What I have found, are that titles seem to be broken into chunks, then ranked on how each chunk would rank, before delivering a result to the serp.
An example of this would be something like:
[brandname] [model-name] [product-type] [action words]
Before Mayday update, it would be ranked based on the phrase:
"BigName MOD8765 Air Conditioner Bargains"
After the update, it seems that each section of the title is being assessed THEN ranked.
HowDoesSiteRankFor - [brandname] = score
HowDoesSiteRankFor - [model-name] = score
HowDoesSiteRankFor - [product type] = score
HowDoesSiteRankFor - [Action words] = score
After these initial rankings are completed, then a final position is sent to serps.
I have seen looking through sites I manage (i know, me, me, me, sorry)
that simply pulling off the brand name, a serp can go from 40ish to top 10. The MINUTE you search with the brand, poof... gone.
Likewise... pulling out the [product-type] can take a bottom 50-ish rank, and move it to top 10 for [brand-model-action] phrases.
So I really think its a cumulative combination of how your page ranks for the "chunks" or the title, that determine where the page ranks for the whole title.
To us, the Mayday update was:
Complex.... fun (got me thinking SEO again)... VERY costly in both time and money!