Hmmm. I hate to say it but using the pelham as shown with roundings I agree with her, it is a blunt instrument. High end show jumping fashion atm seems to be pelham, flash, roundings and martingale!
I use a pelham with two reins all the time, but have only ridden with roundings once. Not my horse, and I swapped to give the rider a rest. She was exhausted after a very strong large native had been pulling her arms out all day. I would never ride with roundings again.
Pardon my hobby horse but as well as being taught to sit on a horse riders need to learn about lorinery. If you know how and why a piece of kit works, and you know the end you want to achieve you can suit one to the other and not blindly follow fashion.