First of all, this cycle is anything but safe, and I would doubt about its effectiveness. There is no doubt that you will lose weight with it, but this is not only going to be fat loss, since you will also lose lean mass due to the fact that both of these things are completely catabolic. Neither is it safe. Keep in mind that clenbuterol was never meant for fat loss, and at the dosages needed for that it can cause a lot of side effects. As for T3 - it is quite a risky thing to take, since you never know how your thyroids can react to it, and what sort of consequences are to be expected. For instance, some time ago I have seen a case of one lady, who was taking T3 for fat loss, and everything seemed to go well until she got a bad reaction to it, and had to stop taking it. Ever since she was gaining weight without control. It is a very delicate gland, so it is very easy to mess it up. Not long ago a doctor I know said that thyroid meds should never be used without proper prescription based on proper testing. Additionally, you have to constantly monitor yourself when taking it.
All in all, I think it is a horrible cutting stack. It is not safe. And the results will most probably not last you long.
It makes much more sense to use something that was at least meant for this kind of purposes. For instance, you can use either Cardarine GW, either SR9009 - none of them will cause side effects, they burn fat and yet maintain your lean mass, and apart from that they have many additional benefits. N2Slin is another supplement you can successfully use for fat loss, as it is very safe, and it is also effective.