mix tobacco with mine, always have done. i think everyone in the UK does.
thinking about it, a joint of pure weed is what 2-3 grams? its a bit of a waste as most of its just burning up.

it helps the weed burn ind i think it gives the buzz a slightly different accent. my joints are generally 50-75% tobacco depending on the weed.

like somone said above, a whole joint of pure would knock me sideways, if it was decent weed, id have to keep putting it out! a whole joint like that would probably last me all day lol