Filling in PIP review form quoting legislation. Yes or no

Hi jakkijax,
Indeed both scenarios have merit. That said I think the answer depends in exactly what you want to quote.
Reg. 4 (2A) reliability criteria. (Safety, acceptable standard, repetition, reasonable time.) I think is always good to mention as DWP is notoriously bad at this.
So eg I need supervision to prepare and cook a simple meal for one. I am unsafe using knives and hot pans because....
Or Reg 7 majority of days and also higher value when more than one task in the set apply equally etc
Eg When I have flare ups I can not do X....because I am so weak I have to remain in bed, and can not even get up to go to the toilet unaided. The flare ups last for 3 or 4 weeks, but can last longer. There is usually a week when I feel a little better between the flare ups. Therefore I can not do X ...for the majority of days.

Or - My condition varies - half the week I can walk 20- 50m before the pain becomes too severe, and I lose balance and can fall and hurt myself. On the remaining days, the pain is much worse and I can only manage up to 20 m. Because I can not walk more than 20m safely, in a reasonable time and acceptably in accordance with Reg 7 - I should receive 12 points- 1e.

I often write these kind of explanations, using a subtle reminder of the law to hopefully steer DWP in the right direction. It does sometimes work.
Don't be overly concerned about looking too smart doing the above.
However unless you are absolutely sure what you are saying don't refer to specific Regulations by name/number, that really will confuse the assessor and potentially the decision maker too.
Regs 7 and 4(2A) should be referred - Reg 7 by its name, Reg 4(2A) by use if the various words, such as safely, repeatedly etc.
I would quote other law (if you are sure and confident) in a submission to the tribunal. (Legal arguments) especially things like Supersession law and caselaw.
I hope this helps.
LL26