chillrobot on "Implicit file upload size limit of 100MB?"

My hosting company, Dreamhost.com, walked me through how to increase the file upload size limit because the methods described here weren't working. Their method involves creating a phprc file:

http://wiki.dreamhost.com/Php.ini#phprc

http://wiki.dreamhost.com/Php.ini#Increasing_the_Filesize_Upload_Limit

Now WP 3.6 shows my upload limit as 360MB (I made it that large because I have hour-long videos). Yet only uploads smaller than 100MB succeed. Is there an implicit processing limit in WP 3.6 on upload size?