We typically just use a headline format where the 1st letter of each word is capitalized with the exception of stop words (when used - but we of course, try to limit the use of these types of words in meta titles!)

I wouldn't have considered that the capitalization could impact rankings, however, I could see where it could have an effect on CTR.

I'm glad I stumbled upon this question to read some of the valuable comments made so far on this topic!

• Amiee