If it was your own child then, you could achieve direct parallel with lots of patience. In my experience of teaching kids from 3-14. I really don't believe you can teach a child under 6 with direct parallel. If you look at that 2 yo, he skis straight, decent balance but no evidence of ability to stop on his own or turn, he constantly relies on dad to slow and stop him. That's the major issue with any learner! The ability to stop/change direction. I've seen plenty of 3-4 yo straight line but turning parallel in the first few lessons is almost impossible.
This is due to physiology...
- the child's neuromuscular system is not co-ordinated enough, some kids are very floppy at 3!
- short attention span - 15min if you're lucky, their first ever lesson, you'll be lucky to get more that 40mins out of them even if they are super keen
- low stamina
- low strength
direct parallel will not work for 3-4yo. Get ready for lots of tears. A edgy wedgie is very useful early on to build confidence, provide a safe environment and help them to stop. Who cares how they learn as long as they have fun, technique is not important at this stages, it's to get them hooked on that white stuff :)) If they leave with a smile and wanna come back that's job well done.
still don't think you can, although they are stronger and better stamina and also starting to understand tasks better. Again focus is on fun and games. No kids this age likes drills!! Terrain games and trees!
Kids can develop as fast as they want or as slow depending on their own confidence levels. So starting in a wedge at a young age, I don't think has detrimental effects on their development in skiing. However for some kids it's really difficult to get them out of one! I took the whole season to get a 4yo out of one, mainly because he didn't want to ski parallel. I've also had 4 yo teams that skis parallel all the time that started in a wedge.
7+ more reasonable age to attempt it and get some success, starting to get better co-ordination esp from other life experiences eg ice skating. Even the most determine kids get sick of falling.