No, you can't do it with minimal effort. There's a reason people say this is one of the hardest trophies, accross the entire PS3 library, to get. I got the trophy last week; my time: 30.68s. This is the method I used; it's the most efficient one. Took me about an hour and a half to get the trophy.

i feel your pain bro - i got so damn close - milliseconds in fact before i gave in- still no closer ot this day

Crazy hard. One day... One day...

Yeah, there's really no such thing as getting this with minimal effort.  What you're doing now is how I did it.  I'm lucky I'm pretty good about controlling any anger I might have cause needless to say I wanted to break a few controllers getting it.  The third barrel roll is a pain but after enough tries you can develop a strategy for it and become pretty consistent with it.  That was honestly my only problem as all the other barrel rolls were fine.  There's a video on youtube I found one night that showed a good way at trying to launch up and get the third barrel roll.  I'll try to explain the best I can.
 
Basically you'll get the inside on the turn right before the ramp.  You'll get to a point where you can head directly towards the far right corner of the track where it ramps up.  Once you ramp off the track (you should be to the right of the overpass) very quickly aim your ship left and go for the barrel roll.  You SHOULD be able to get the barrel roll, land on the the overpass and straighten yourself out.  There's really nothing you can do right now to make it less hard you're just going to have to keep trying until you get that lap where you do everything right.
 
I hate hearing people say it cause I felt like it didn't help me but the following is very true.... keep trying, you'll get it eventually.  It took me about two nights of 4-5 hours play sessions (with breaks :P ) to get this...but once I did I was one happy camper.