I don't think Phil is miming and, if he is, he's not doing it on all the synth parts he's obliged to play (or look like he's playing).
There's a fair bit of kit still on-stage with them at the moment. They used to cart around several synths, a rack of effects, samplers, at least one drum machine, a keys mixer and a sequencer. That's been slimmed down since the Get Ready gigs to Phil's Roland XP-80, an all-singing, all-dancing 'workstation' synth. Steve uses a Kurzweil synth for his parts, although I think he's switching programmed drum patterns and maybe triggering samples too.
Barney uses another synth on Blue Monday only really but I've seen him share one with Gillian in the past! The other 'new' synths on Phil's rack - one's a MonoMachine which is a new one on me and I'm a synth nutter! - which was MIDId up so I take it it was contributing layers here and there. A good deal of the synth parts are sequenced or maybe recorded on their hard drive recorder (which sits to the left of Steve's drum kit; you can see it on their various TV performances).
Phil breaks off from playing guitar on Krafty to play the bells bit so one would think he was actually playing it rather than miming. Barney must've improved as a musician overall because he can now sing and play at the same time, the majority of the Order's past material being typified by him singing inbetween playing!
Using any kind of recorded media or live sequencing poses a question over what you play live over it and what would either sound better sequenced/recorded or played live. When I gigged with a similar setup, I preferred to alternate so I was playing a bassline on one song, chords on another and a lead part on another. It's up to them really.