Easterhay said:
And yet didn't McCallum try to discourage Lucas from a totally CGI Jar Jar in TPM purely for monetary reasons?
IIRC, in the behind the scenes footage on the DVD, they mentioned having spent a huge amount trying to make a Jar Jar suit work, before ILM said they could pull it off digitally.
Ahmed Best still wore most of the suit to interact with the cast, and for benefit of the FX crew to blend the CGI elements in later.