I think they will honour the warranty if you chop it provided you don't claim for smething you cut off! I don't think there is an official guide. Try under Product/7 key Functions 1st bit leanweight design.
So you can chop the lid, the waist strap including handy pockets, the side mesh pockets and the front mesh pocket. Oh and you can ditch the duomat from inside. Less serious would be losing the chest strap shortening any straps and cutting off clips and other odds n sods.
But really why bother? They are for the most part all useful and should you wish to sell it you might struggle o find a buyer.
Adding to Matt's VR list I've got a Tour Lite (I think that's the name). It was designed for ski touring and has a small sleve pocket for a lift pass, pit zips and napoleon pockets and a hood which I think is helmet compatible. Not long though, just over the bum with a bottom draw cord.
I reckon a helmet saved my life. Years ago I was in a motorcycle accident where a woman pulled out in front of me. My head/helmet hit her bonnet first, I woke up later in hospital. Can't say for sure no but I'm glad I had one on. Similarly I've been knocked unconcious twice in cycling accidents, both without a helmet. I always wear one now and whilst I haven't had so serious offs I've not managed to knock myself out since!
Walking, I wouldn't bother unless coming off a hill in winter and it was just still on my head. (I'd put one on if there was a risk of me sliding or falling a long way or people above kicking stuff down).
Tall PC it would seem obvcious that any organisation run not for profit would be - provided it was managed correctly at least as good as a private one but either costing less to use or offering a better service for the same money as there is no requirement to pay a huge chunk to investors.
Privatisation started with obvious money spinners and then dogmatically proceded through the list of state owned industries. In the case of rail First Great Western for example are running the same 40 year old rolling stock but with more seats less frequently more slowly for a lot more money. Energy as already mentioned has had no significant new build generation (apart from wind) in a generation. Nuclear - which had to be sold off with a sweetener of the Gov picking up decomissioning costs to sell it in the first place is a shambolic mess as private companies - all foreign, argue over sweeteners.
Unfortunately the witch may be dead but her legacy lives on.
I'd suggest ML is a basic qualification and should be treated with caution depending on what the holder has or has not done. MIA is a lot more relevant as a minimum if you want to pay someone in winter.
Guides and courses are great and can impart a lot of knowledge in a short space of time but as said earlier there are no short cuts to gaining experience. The plus side of formal training is you should expect to learn current best practice and possibly avoid making some dangerous mistakes. Not that there's anything wrong with dangerous mistakes, they add to lifes rich experience. Provided you live to tell the tale.