We've just received the Statement of Reasons for my caree's appeal - it was very illuminating.
Brief history: caree with a fluctuating condition transferring from DLA to PIP, originally awarded zero points in both categories. Certainly deserved 12 points in the mobility category as unable to mobilise more than 20 metres. Caree (C) also housebound and therefore couldn't attend the appeal. First appeal session adjourned for non-attendance: tribunal directed DWP to submit paperwork for previous DLA and ESA assessments (they didn't); directed us to submit evidence from GP plus C's medical records.
I wrote the request to the GP, hoping to give her some indications of the points we needed her to address: she was very keen to help. Unfortunately, she misunderstood the descriptors, and what she wrote was not very helpful. I winced when I saw it, but because the tribunal had directed us to submit it (and we were very near the deadline, so had no time to revise it) I believed I was obliged to send it in. GP's comments were that C in the past decade could "rarely" walk 200 metres, and that she "often" requires a wheelchair to go any distance.
As I've probably pointed out on here before, GPs are rarely in a position to comment on how the PIP descriptors affect a patient's life, and this is an excellent example of how a little knowledge can be dangerous. She has no real idea of how far C can walk, having never seen her walk further than from the surgery waiting-room to her office, or how her condition affects her ability e.g. to prepare meals, etc. She'd obviously read an overview of the PIP process and decided that although she perhaps couldn't commit to saying that C couldn't walk 20 metres, confirming that she couldn't manage 200 metres would be enough, because after all, 200 metres is the limit beyond which you can't claim, isn't it? As a professional person, and clearly being reluctant to commit herself to anything she couldn't be certain was true, she was over-generous in her estimation of how far C might be able to walk. So her "evidence" actually contradicted, or at least undermined, C's case, indicating the possibility that she might on occasions being able to walk 200 m, and didn't necessarily always need to use a wheelchair to go out.
Result: at its second session (again unattended), the tribunal found that C was entitled to standard rate mobility because her ESA had her in the Support Group as being unable to walk more than 50 metres - but not the high rate, which she should have had. She's now gone over pension age, so can't put in a fresh PIP application, but is stuck with this low award for the rest of her life - or at least until such time that the Government moves the gateposts again and decides to reassess even the older claimants.
So, if you can, be very careful what you submit from your GP. It's difficult, but if you have time and the opportunity, go over it with a fine-tooth comb and see if you can get it amended if there's anything that might harm your case. Hugely difficult given the pressure on GPs to do other things, though.