Many gamers will - with justification - claim a loss purely on bad dice throwing in critical phases of the battle (such as when my velites disappeared in moments after throwing 1,1 on the first cohesion test and then got battered in the subsequent melee).
And as dice have such a key position in determining wins or losses, it is not suprising that many arguments stem from how the dice themselves are thrown. Seeing your opponent knock off 6 after 6 with what looks like a 1" drop onto the table is bound to lead to accusations of jiggery-pokery and demands that a certain height be employed and that the opponent gives the impression of 'shaking' before release.
Similarly rolling across the battlefield often sees the dice roll up to the side of a piece of scenery or block of troops - leading to counter claims that the dice has landed on a scoring 6 or a wayward 2.
For this reason dice towers (such as the one I made a way back) or other constructed receptacle for dice to be tossed into can take some of the rancour out of the dicing element - but only if both parties agree to use the item in question.
An alternative option can be considered though. Providing both parties use different dice colours a fair solution would be for one of the parties involved to throw ALL dice in a combat. So assuming that we're playing FOG and there are 8 dice to be thrown for Impact, then all 8 are placed in a cup (or the hands of one player) and rolled by that player (who can then hardly be accused of influencing his own dice to the detriment of his opponent). The next combat sees ALL dice passed to the opposing player to throw.
Of course, it can be hard to see a key combat take place over which you have no influence (as your opponent rolls the bones of fate) but it could make for a happier gaming table.