Yes I... to continue...
In thinking about what it is precisely that I get out of using ganja, it occurs to me that most of the perceived benefits are really enhancements of things that are enoyable/get one "high" by themselves. Music (which can definitely get you "high" by itself) is perceived more deeply and richly, or so it seems; dancing to it and/or chatting lyrics on top of it can become seemingly effortless and graceful. Food that tastes good can taste even better. Sexual experiences can be intensified. Etc... so I think that's the common theme running through my positive experiences with ganja: it can intensify an experience that is already positive to begin with. The potential negative effect here would of course be diminishing one's ability to appreciate the experience by itself, without the enhancement that ganja provides. However I've found that most negative effects of ganja are caused by over-use, and that there is a sort of built-in mechanism against overuse with ganja: simply, the more often you use it, the less "high" you get, and if you use it way too much consistently you even start getting "low" rather than "high"; most of the positive effects you're looking for aren't there any more besides a low-level, quickly-fading buzz which tends to be replaced by irritability (in my case). That's when you know you're smoking too much and need to take a break or cut down. The more occasionally you use ganja, the greater the rewards, so there is a built-in mechanism to discourage over-use.
To go over benefits/costs in a few more specific areas:
BENEFIT: can provide the feeling of connection to "non-ordinary reality", whether you want to call it the spirit world, the child's eye view of the world, or what have you; but to a lesser extent than some other substances (psychedelics), so that one is still able to function adequately in "ordinary" reality. COST: Can sometimes lead one to "drift" a bit too far from mundane concerns; could possibly diminish one's ability to get in contact with "non-ordinary reality" by non-substance-related means.
BENEFIT: Not nearly as addictive as most other substances out there; if you feel you're using too much or it's no longer beneficial to you, it's pretty easy to cut down or quit with no (or very few and mild) withdrawal symptoms etc. COST: Although not physically addictive in the same way that alcohol or nicotine (for eg) are, can still be habit-forming and the habitual side of it may cause one to use more than is good for one (I am an example of this to an extent; there are times when I carry on smoking too much/too often although I realize the fact that I am getting diminishing benefits).
BENEFIT: Can create a quiet, meditative, reverential state of mind with which to appreciate being in nature and to explore one's own inner space (this is related to what I was talking about in part one as well). This can manifest as an overwhelmingly happy, joyful feeling but can equally well manifest as a kind of wistful melancholy kind of feeling (hard to explain... like being homesick for a different reality, but in a good way...) Both feelings come under being "high" to me. COST: Could lead to depending too much on the substance to access a state of mind that can be reached without any substance (although, in my experience, not as predictably - i.e. I get into "mystical reverie" kind of states of mind spontaneously and have since childhood, but at random unpredictable times; whereas the combination of good ganja and being out in nature will take me right there right away.
BENEFIT: Increasing focus on a given activity [usually a creative activity for me, but could also be sports/exercise as I find a bit of herb goes well with working out; I also used to smoke a bit when I used to do a lot of repetitive manual labour type jobs, it seemed to make the day go quicker and it would be less boring, I'd just focus on the exercise aspect of the work and have my own little movie/soundtrack sort of thing going on in my head whilst getting on with it). COST: Smoke just a little too much, and you lose all the focus you gain. Also, you will automatically lose focus on any intellectual task that you are not already interested in (can increase focus on things you are interested in/know how to do well but decrease focus on things you don't know how to do so well or are less interested in, which could actually be the things you need to develop the most).
BENEFIT: Can enhance feelings of camraderie, friendship and humour/laughter with your friends and loved ones. COST: Can also cause one to go into oneself perhaps too much, to the detriment of one's relationships. This aspect is very much a double sided coin. I've found ganja can make me more sociable, or more introverted, and I think it depends on the state of mind I'm already in when smoking, as opposed to most of the other positive/negative effects where the less often you use it the more positive and less negative effects you get, I don't think this aspect has much to do with the frequency or amount of use. Then again, everyone needs some balance between being intro- and extroverted, so it's not necessarily a bad thing that it can encourage both.
BENEFIT: Tastes nice, smells nice, looks nice and just seems like the right substance to use if any! COST: Overuse negates or reverses the enjoyable effects.
Well I gotta get off the computer... I suppose I could go on thinking of perceived benefits and costs but the above is a decent general overview of how I feel about it I think.
Ayinde, it's a good point you make about personal experiences and I will bear it in mind, but I still think I'll return to the thread sometime to give mine; whoever wants to distort things can go ahead and do so, and I'll counter the distortions as they come! Probably won't be for a while though as I don't see myself being on the internet too much over the next week or two, lots of things to do.
Respect