I see this as several different issues:
Firstly, what is the benefit of raising natural production of Test by 146%? As I understand it strength may go up a little and endurance some but not the production of RNA. No dramatic increase of protein synthesis worth mentioning leading to significant nitrogen retention for quick muscle repair and growth. AAS are derivatives of the steroid Testosterone and are unique in that they do these things for us. You are able to hit the gym harder longer and sooner because of two biochemical reactions stemming from the production of the enzyme RNA. These reactions are Creatine Phosphate and Protein Synthesis. Creatine phosphate is responsible for energy conversion in the absence of oxygen. This is why you can lift sooner after a heavy set having very little recovery. You are in an Anaerobic state and have less oxygen pumping through your veins. The other is protein synthesis. This is tricky to explain so in a nutshell you are shuttling information to receptors in a new format where it undergoes transcription (a decoding process of RNA and DNA into a new understandable language for the body to identify and use the protein. Sort of a translator of different languages into a single understandable code if you will). Protein synthesis is how we maintain a positive nitrogen balance allowing for quick recovery and growth. In order for AAS to be effective we must be in a state of positive nitrogen retention. This is where the mass comes from. Not from extreme natural test production. It is from the secondary effects of the AAS that we gain strength and mass.

Secondly, Letro suppresses estrogen production by up to 96% and even though this does clinically increase LH and Natty production it it also suppresses estrogen. Did I mention it suppresses estrogen? Estrogen is responsible in part for libido, HDL (good cholesterol) which is responsible for a healthy heart and not new to women everywhere bone density. Study's are showing that prolonged use of AI's may lead to early onset of osteoporosis and heart disease. The article referenced above mentions taking this stuff for a year. It might be worth mentioning that Letro is a 4th generation AI that is used as a last resort in post menopausal breast cancer patients after extensive courses of tamoxifine or clomiphine treatments have failed. Letro has its applications in BB for reversal of pre-existing estrogenic gyno (that's the one with the hard knot behind the nipple) and progesterone gyno (build up of fatty tissue around nipple). However, it is not recommended to take for lengthy periods of time. It can actually be painful if taken for too long as it tends to dry out joints drastically.

Thirdly, lets talk a little more about estrogen suppression. By suppressing the body's natural production of hormones we take our bodies out of homeostasis (my favorite big word). As a result of this when we discontinue any hormonally suppressive drug including AAS; our bodies scream to get back into balance. This means working overtime to increase natural production of estrogen in this case. Which means excessive free range estro floating around. If I am not mistaken that can lead to gyno right? Typically there is a nolvadex regiment after a course of letro to combat rebound of estrogen. There is nothing in the article mentioned above that suggests any course of action to combat this scenario. How is any of this beneficial to a young man. If they are going to take drugs regardless of warnings from veterans and older more experienced people than in my opinion the lesser of the evils would be to take a very minimal dose of test and some nolvadex tapering off and a simple PCT. Maybe not even that.

My name is @#^!& and I approve this message! Um..maybe....

If Letro was the key to increasing natty T production, it would be THE go-to choice for TRT patients.

Sorry mate, bad advice here.
There was a fad I heard about a while back, It was very similar. It involves using HCG (doing the same as the letrozole thing).
Sadly, it doesnt work.

Youngsters should be learning how to eat and train, when they learn to gain size as a natural, then when old enough, progress into a low dose testosterone only cycle.
From there... Depends on their "realistic" goals, simple test/deca cycles (500mg/500mg ect), are more than enough for common guy who just wants to look good, plus these drugs have been around for decades and have tons of research to back em up.