Benelli described a periareolar breast lift technique that bears his name, yet many surgeons perform some sort of periareolar lift that differs from the details Benelli himself describes. In other words, some surgeons do a slightly different lift technique, and also use different suture materials, each of which can have a bearing on the answers you are receiving. Every surgeon who DOES something different will be truthful in SAYING something different.
Here's the skinny: If a premanent suture is used (like Benelli described), there will be less (theoretically none) areolar stretch, since the suture does not stretch or dissolve. Obviously, there are still limitations to the amount of "lift" that can be achieved with this procedure, and the net result is usually some degree of areolar flattening, as well as some degree of scar irregularity dependent upon how large of a circle is "purse-stringed" to a small(er) diameter areolar circle (Hence, the minimal degree of lift possible).
To avoid the visible suture (which can sometimes be FELT as well), some plastic surgeons have used other suture materials. Disssolving sutures lose their ability to "block" the areolar stretch that always occurs without a permanent suture, so some surgeons choose a very long-acting dissolving suture like PDS, hoping that the healing and stability of the suture line is established if the stitch is present for "long enough." I have tried this, and it generally doesn't work. Shorter-acting dissolving sutures are even quicker to allow areolar stretch, which is not only faster but more severe!
So most of us who still perform Benelli or modified periareolar lifts in select patients will use some sort of permanent suture to avoid the stretch, but unfortunately which can be seen or felt in some patients. I have found the best compromise between these opposing issues is satisfied by use of a Goretex suture, which is a permanent suture, but one which is microscopically porous to allow tissue ingrowth and fixation, and yet soft and somewhat "stretchy," which decreases the visible and palpable suture presence after this kind of lift. This is further enhanced by trying to place the suture in the deep dermis and taking many small bites with the suture. Still, some patients have thin skin and the stitch may become visible, especially after swelling diminishes!
I presently perform few Benelli or periareolar breast lifts because I do not like choosing between these two not-so-desirable alternatives, and because if you are a candidate for a minimal lift, you might well be a candidate for no lift at all. If you really need a lift, then you may be better served by a "full" lift that truly shapes the skin brassiere and repositions the nipple/areola complex to its "proper" higher, lifted position. Best wishes!