Not sure I agree with that. Obviously you shouldn't buy one unless you're sure you'll play the game enough to get your monies worth but even an inexperienced player will generate income with a premium tank and it will really help you early on having a tank that can bring in the credits to afford your new tanks, crew training, modules and any equipment you want to purchase. Equipment won't make a crap tank good but it will make a good tank even better.
The best thing IMO would be to get a premium. Try and play in platoons with us to learn your tank. Learning to play a T8 tank on your own will set you up for a long road of heart ache.
Play with us, listen to what people say to and don't take offence if we tell you your doing something wrong. I still get told, everyone does, your always learning. Trinidad is the perfect example. He did actually wait until he bought a T8, he worked his way slowly up, and he is 100% better than he used to be, but he does toon up with us every day, he plays he companies and does well.
We have TS, come join us, you will find it hard to progress fast on your own.