Hi, not sure why you would need to use this device in Scotland but each to their own and with this in mind, have you purchased new osprey reservoir as they have changed their design to allow you to remove reservoir and leave hose in the pack, see link.
https://www.ospreypacks.com/user_manuals/OM_Hydration_S16_ENG.pdf

Thanks, Byron. My reservoir is only one year old but is a different design and doesn't easily detach from the tube.

On the question of whether or not I need to drink water when hill-walking in Scotland, yes, I do. I would be surprised if I were alone in this! Don't you? :)

Vanessa, I only carry a small 0.5L plastic bottle for water (and only use it when really needed)... I'm more inclined to drink straight from a fast flowing burn or river.

Cheers,
Bernie

Wow! Only just seen this. I guess you must be more of a camel than me. Or I sweat and pant more. So far on this challenge I have drunk each day between 1 and 1.5 litres from the platypus plus between 4 and 8 cups from streams. And the output is infrequent and not that light. I've always been the same so it's not a problem (except the weight).