Some do get their legs un-tangled faster than others but it still takes them awhile.
Also, as Appymom commented, it is not uncommon for them to have a sudden and big growth spurt right when you think they're done growing.
My Generator-bred gelding had a huge growth spurt between 6 & 7 years.
What I might suggest is to watch the horse you're training at liberty. Get her to move out in the pasture or arena, with nothing on her. Watch her leg movement.
When her leg movement stops being gangly/all in a tangle and she starts moving with fluidity, she is getting her legs co-ordinated with her gaiting birth right.
When one of my TWH's was a youngin', he would get his legs in such a twist in the pasture, that I marveled how he even stood up
He was coming four, by the time he grew out of that and he did have a beautiful, natural running walk under saddle.
I also agree to walk walk walk walk walk and walk some more.
My apologies but I do not agree with starting a 2 year old under saddle - never have and never will, unless it's being worked from the ground