Our guys used Flechettes in 105 howitzers in VN, esp. on the hills defending Khe Sanh.
There was one NVA attack, possibly by a company sized unit, that took some 105 flechette shells head-on.
The AAR in a book on this battle said that there was nothing left of the NVA company. They had been shredded into raw meat.
This was a level-aimed barrage at a charging mass (which became a dead mess).
I agree that a mix of VT and impact fuzed shells is a morale destroyer, but when the enemy is closing in fast, you can blow them away with flechettes (which we no longer have in our inventory - Another DOD/Army planning fiasco).
“They had been shredded into raw meat.”
I always love a happy ending.