Yes, and when a tank is using the +25% camo module, and the crew is rated at 100% overall experience and receives the additional specialty slot filled %100 camo experience, a tank goes into stealth mode rather quickly, and can sneak up and fire on you in camo mode from short distances.
There are a lot of flaws with WoT that is for sure, and this is one of the big ones imo. I hated it at first but managed to get past it because I was enjoying myself so much. Today I know all about the camo feature and use it to my advantage.
I've noticed in a lot of the tanks in game (at least the ones I've played with regularly) you can usually use players camo against them- ie, if they disappear from your view, 'troll' them a bit and they usually pop right back up. Send a shot toward where you think they are or have a buddy in artillery send a shot in that direction. Most players, no matter how well hidden they are, will think they're spotted, panic, and high tail it to 'better' cover- in the meantime, you can usually spot them and get in a good shot or two while they run away. I've used that trick to flush out a lot of lights and mediums, and then either pop them in the open or track them for others to finish off. Doesn't work so well against the heavier stuff, but that depends on the player too. A lot of the heavy tank and TD snipers are paranoid about losing credits in their high-tier behemoths and will fall back if they start taking too much damage.
Then there's always the time-honored 'have a buddy hold their attention while you get behind them' method. Usually not conducive to long-lived buddies, but works pretty well, especially if you have the gun to take out their engine or light them on fire with the first shot or two.