Joking aside. I really do think using the left thumb is by far the best approach to rudder 'mixing' in turns. I'm not anti-computer Tx mixes, I use them on all my models for certain things, but the advantage of using your thumb in turns is that you aren't stuck with a fixed rudder input but can vary rudder deflection as required through the turn. Probably more important is that under use of rudder is the biggest failing in RC flying for many if not most flyers, so anything to get the lazy thumb working is a good thing.
Dont take my word for this. Scott Stoops is a world class aerobatic flyer of both RC and full size aircraft and the author of the worlds best book on RC flying (IMHO). The book is called "The Pilot's Guide to Mastering Radio Controlled Flight"
Here's a quote from the book:
Another mission of mine is to increase the manipulation of the left stick by RC pilots...... The rudder is without question the most underused and misunderstood control we have. You've got a throttle and a rudder, lets lean how to use them