I was listening to
during the run-up to 7e, and I was very confused not to hear one particular idea about pushed rolls: might not a pushed failure be something akin to a fumble? Nobody ever seems to mention this possibility, but (speaking as an occasionally hard-pressed GM) there are already four possible outcomes to a roll (fumble, fail, succeed, crit) and I don’t really want to have to think of other complications on the fly.
That in turn is why I am a bit dubious about new Star Wars / Genesys (the constant pressure on the GM to come up with little extra bonus/malus effects), though one of the WH crew has the latter and hopes to try it on us soon.
Certainly when the Esoteric Order of Roleplayers were playing Achtung Cthulhu
http://esoteric-rp.blogspot.com/search/label/achtung%20cthulhu
they misinterpreted the rules to allow pushing or luck spending, and they definitely preferred luck spending when they had the option.