well, how you sketch transform then?
**note** this must be done on ruby/saphire
1. Get into a double battle with ditto and another pokemon that knows spore (it's easier if smeargle knows spore). Smeargle
MUST be faster than ditto.
2. Use spore on ditto.
3. Have smeargle use sketch on ditto. (smeargle has now sketched transform).
Whenever a pokemon is asleep.... the move it was going to use is still counted as sketchable in ruby/saphire. Since ditto tried transforming on move 1 but was put to sleep beforehand, he used the move but to no success.
Smeargle cannot sketch transform unless ditto is asleep. Once ditto transforms, it no longer is considered to have that move and thus cannot be sketched. This is why it fails when people try it any other way.