Regarding the issue of tank speed.

[sage ingot]

This is the Penetration Status of the Front Armor and Ammunition Rack Vulnerable Areas of All Main Battle Tanks in the Current Version

• Red boxes: Areas that can be penetrated.
• Blue boxes: Areas where the ammunition rack can be penetrated.
• Yellow boxes: Partially impenetrable areas (only applicable to the "vibranium" observation windows of Russian-series tanks).

Notes:

1. The frontal hull of the Type 99A is invulnerable in the current version (anti-tank rockets with heavy warheads and TOW missiles cannot penetrate the area below the frontal turret).
2. The Leopard 2 has a significantly increased hull protection area.
3. The T-90’s frontal hull bounce zone has been removed.
4. The ammunition rack of the 1128 has been adjusted to the infantry fighting vehicle (IFV) mode.
5. For positions that were penetrable in the previous version but are now impenetrable, a penetration effect will still appear upon impact—but no damage will be dealt!!!

The test was conducted using 800mm penetration AP rounds (armor-piercing rounds), the mainstream ammunition for main battle tanks.

[gritty canopy]

Most of the issues with tank armor are probably related to desync, especially when the correct fx is played.

I did not test it myself, but it sounds like the damage was not applied correctly on pen. This happens to other at weapons currently.