This question takes place in the same setting as that of this post (tl;dr: the world is bathed in thick magic fog, the naked eye can't see past a hundred meters, an M4's effective range is 50 meters, advanced electronics fry if not fitted with expensive shielding and even Blue's best radios are underpowered and unreliable).
Blue's armored force is made up of 5 main vehicles: a light APC, a relatively light tank with a 30mm autocannon, an assault gun variant, an AA variant and, finally, the "Glory Hog", a stripped down Merkava MK IV with a 125mm gun, a light mortar, good frontal armor and, most importantly, enough space to cram 10 elite infantrymen in the back (and they're so brainwashed they won't even care if they're squished like sardines!).
Originally, I- ehrm, Blue high command hatched this idea as a cost-saving measure - why build two metal boxes when one can carry both infantry and a cannon? -, but then I also noticed a secondary benefit: self-reliance.
Combat in this setting gets extremely messy and chaotic, and deep penetration is usually hampered by poor communications and coordination - practically speaking, it's extremely easy for tanks to get lost from the infantry and be left almost helpless. But if a tank carries its own infantry, its own artillery and its own supplies, surely this will be mitigated somewhat, right? Does this make any sense at all?
(EDIT) Point taken. Allow me to change the question a little: is the concept so egregiously inefficient that it wouldn't just be suboptimal but downright ridiculous for it to pass? Due to historical reasons, the infantry branches (and infantry officers) of the Blue army are the second most respected branch by far, only bested by the almighty logistics corps. Could it make sense for a tank like this to be approved largely at the infantry's behest, founded on fears of tankers "charging off who knows where and leaving the real fighters to rot" and would it actually be a good idea from their perspective?
(EDIT 2) To clarify, the infantry isn't meant to sit inside the tank and eat compressed biscuit until whoops, we all died. Whenever the tank is in a dangerous area (and especially when it's actively in combat), they're supposed to dismount and fight like normal infantry (that knows the limits and tactics of their tank support very well). They would only mount up under the same circumstances where conventional mechanized infantry would enter their APC, like long-range drives or if they really, really needed the armor. Apologies if the original wording was misleading.
(EDIT 3) The tank's main gun can reach out to 200 meters (the optics are still only good for a hundred) and the mortar can hit out to around 150 meters.