push the envelope
"stretch the limits" - to go further (in any field) than anyone or any group has done before. perhaps doing something that wasn't previously thought possible.
Example:
dude, that quadruple-backflip double-twist one-handed going backwards while blindfolded and sucking a lolly (deep breath) surf manoeuvre was really pushing the envelope.
dude, that quadruple-backflip double-twist one-handed going backwards while blindfolded and sucking a lolly (deep breath) surf manoeuvre was really pushing the envelope.