This discussion will never end!
As Starsky said: if you've learned on short struts, you're probably convinced it was helpful or an imperative.
If you learned on full size strut, you think it's not necessary.
What we'd have to have is quantitative data on " hours to learn to fly 100 m in each direction without touching down, be able to do that with controlled stop, using a full-size strut "
With and without using shorter struts.
Now I just learned on full sized strut, was able to pass the test on 5th session ( 6th hour). I cannot see how using a shorter strut would have made it faster to learn.
Bear in mind I was CONVINCED that I need a shorter strut at 3Rd hour.
But I did have private, radio based instruction in near perfect conditions ( wind was light and gusting) for hours 4-5-6-7.
So I'm convinced that professional instruction with radio accelerates learning