Let me start off by saying that everyone is different, and I am NOT recommending running tren alone. With that said. I have run about 10 tren only cycles over the last 6 or so years. Why, you might ask.....well, when I followed the normal protocol of running tren with a test base, I got every conceivable side effect, so bad in fact I had to cut a 10 week cycle down to about 7 weeks. After reading an article by a pretty well known "guru" about tren and how the conventional thinking might be wrong (about how harshly it effect HPTA ect ect), I decided to run a short 6 week 75mg eod cycle for some real world experience (my goals were to diet pretty hard....I wanted lean, and was happy with my overall size)...needless to say I feel in love with tren alone. I gained strength, dropped bf, and talk about hardness, I felt like steel. The kicker was, I had virtually NO SIDES. Aggressivness, and the loss of cardio ability were about the only things I noticed. I of course ran PCT, but still swear to this day that tren does not shut ME (I emphasize ME) down on its own. In fact I tend to keep gaining strength for 4-6 weeks post cycle, then taper off without any loss or rebound effects. I even had extensive bloodwork done 3 weeks post cycle a couple years ago and my test levels were right in the middle of normal range. My cholesterol was a bit wacky (especially since normally my profile is great) so i had to redo that portion of the test 4 weeks later and it had returned to normal.
A couple years ago I decided to stop sharing my real world experience with tren as a stand alone due to the flaming I would get from guys on these sites (none of which had ever even tried tren solo). So keep in mind that I am not advicating trying this....I know everyone is different and maybe the conventional wisdom is absolutely 100% correct and I just happen to be effected slightly different than the normal. However, my personal oppinion is, is that most people on these sites are repeating info they have read or heard, along with personal experiences of adding tren to a previously experienced compund and noting the new "sides" that the tren is bringing on, and assuming that tren is the lone culpret when in fact (again, totally my opinion) it is a synergistic combination of tren and test that is exasperating all the negative sides.
So to answer your question with real world experience of what to expect with tren as a stand alone (since I am one of the few I know who have actually experienced tren alone). I typically run a moderately low dose of 40-50mg ED for 6 to 8 weeks. I always have run this as a cutter (so I am calorie restricted). I usually range anywhere from loosing 5lbs to gaining 5 lbs during this time (depends on how much bf I need to drop). Strength usually goes through the roof (to the point I need to actually back off a bit and train smart). I also have noticed that tren seems to eat away my belly fat (visceral fat maybe?) I love running T-3 with it....I am to the point now that I just run otc pct products even though I really dont feel like it shuts me down at all (no losses post cycle, no libido issues, no ball shrinkage ect ect).
I hope I helped (and dont get flammed to bad for it)
good luck
Rizz