Letro isn't the only way to chemically treat gyno; that is a myth if you spend some time over at pubmed (no disrespect TG; it's just that I see this comment a lot on the forums). AIs have slightly better clinical outcomes than SERMs I think for gyno reduction based on the studies, but neither is a guarantee and usually the gyno just reduces in size at best (which isn't bad).
I've tried letro at 2.5mg/day for a while tapering up and down and onto a SERM for rebound E2 and it didn't work for me. I know of several others who it didn't work for either. YMMV.
I think raloxifene is a better choice to try for gyno resolution/mitigation-no adverse effects on lipids, can be used for long periods of time since it's a 2nd gen SERM with much less toxicity than nolva et all, and without the horrible joint pain of high dose letro. It actually improves bone mineral density unlike AIs and is FDA-approved for osteoporosis. I'd also be more inclined to try ralox first if you are off cycle; maybe letro or letro and ralox on cycle if needed.
I hear some good things about combining letro and caber to wipe out gyno, but I haven't tried the combo myself.
But chemical treatment of gyno by any means (SERM or AI) doesn't work for everyone. I've tried lots of sheit (Aromasin, cabergoline, pramipexole, Letrozole, Nolva, Toremifene, Letrozole, etc). I got some symptom resolution (my nips didn't feel like they were covered in napalm), but little else. But mine isn't so bad yet that I feel the need to plop 5K on the surgery.
Gyno is one mean whore.