What a load of nonsense!
Do yourself a favour and learn in a trike. It will likely be cheaper and certainly easier.
Then go get a tailwheel endorsement with an instructor who can actually really fly a taildragger - not just take you through the motions of a tailwheel endorsement.
The best taildragger pilots I know all learnt in trikes (cause that's what was used for
ab initio!). These guys can make a taidragger talk!
Mastering the little wheel on the arse WILL make you a better stick and rudder pilot - but you don't need to do your
ab initio on one to achieve the same result.
R