Well.... there is a obviously a strong reason as to why meth is so dam addictive!.... It's fukin AWESOME!!! I am a daily user, and i get literally pure uncut shit from a talented cook. im still surprised the insane potency compared to the rest of the stuff thats around. In that regard, being as nice as it is, its probobly more of a bad thing! as im just messin myself up harder! I can tell you the addiction is Very Deceptive! and WILL bite you in the ass! Really Hard! if your concerned about maintaining what you ahve going on in life, i.e. a job etc... dont link usage! thats my main advice right there! once you link your usage do you get really deprived in you basic, critical essentials, like malnutrition, sleep deprivation etc... and yah, you wont sleep for up to week easy if you just have a dally approach, end of week, you can only image what the crash is like, and how long it takes to just recover from the crash! and tahts just from 1 week. lol, but if you only do it like on this day, maybe two, 3 days at the most! then make sure you take long enough break to feel that you have normalized and dont feel any leftovers in your system, then its up to you how you wanna use, as much as you want, as addicted as you want, but linking day after day is just really bad idea.
More to your question...
i would say as long as you feel in control and have more reasons to do it than caving into temptation, i suppose its different for everyone obviously. in that regard, i could only assume, if you feel you can do like once a week and manage and feel healthy! Feel Healthy, not think you are, you will know when your system is fuked up and outa wack! haha, but if you feel that all is in control and regular afterwords, your on a good track i think. Of course that is all in disregard to the brain chemistry and receptor alterations etc.... that one is going to always be there, and be up to you to know how much is worth it or not. I suggest taking good amount of magnesium citrate! not only to keep tolerance down, but keep the levels in your brain in check, otherwise calcium levels go thru the roof, and magnesium isnt sent to your bones in proper amounts. Also Fish Oils (Omega-3) is health for your brain, plus its a great potentiator! then like take ibuprofen before you do meth to help reduce damage. If you like to snort, make sure to powderize that shit! otherwise your practically snorting super small shards of glass that will shred up your nose more. or nasal spray will help reduce the erosion of your nose. ultimately it comes down to, unlike the healthy/natural drugs such as weed, this is a very serious/synthetic one for more than enough reasons. There is no way to ultimately avoid the "take at own risk" part of the deal.
Anyways, sorry for long post, idk how i wrote so much, despite the fact im obviously tweakin haha. but just wanted to attempt to share some imput from a daily user. Also, for me i've noticed i can do a line, then like few hours later go to bed, literally, i can fall asleep high as fuk. then wake up 1-2 hours later high as fuk!, feeling like i must have slept for 12 hours, refreshed and very tweaked out haha. over time i've been able to regulate better, like eat/drink and sleep.