while flash 4 syntax is deprecated they both work relatively the same. It's only when the processes reach over 6000+ per second that's when things get quirky. the deprecated flash 4 syntax tell target actually works faster than dot notation. let's say for example, dot notation:
1. go to the store, buy eggs
2. go to the store, buy meat
3. go to the store, buy salad
while tell target
1 go to the store, stay in store.
2. buy eggs
3. buy meat
4. buy salad.
for a computer and humans in general such subtle differences do not really matter. But when it goes on an on for thousands of more processes and loops it's 'comforting' for the flash player to know that it's still in the store. instead of getting annoyed by redundant information.