Sounds like there are alot of you doing this! Some people strip one inch, some a 1/4... If you don't leave some insulation on it, the strands splay out. Loosening the connection.
I just don't think this type of terminal is well designed for stranded. As the Spec grade, actually say, for use with "#14 -#10 solid or stranded" on them. Where as this type say, "#14 - #12 CU" No mention of the type of wire. They kind of leave it in the air don't they? Yet they both share the same UL file #, nothing to check there.
Fork terminals are just plain unproductive. No need to go there.
Prefferably, I pig-tail in solid. Really, I'd like to spend the extra 25 cents or so, and only use Spec Grade. Most of which have pressure terminals better designed for stranded. Like most gfi's have. That say,"#14 -#10 solid or stranded" on them.
