A blademaster with archery training over 6 has still 30% critical on his bow, if I train path of the blade the critical chance on the bow isn't specified. Moreover there are many items (Bonecleaver Shield +25%, Scorched Girdle 5%, Fetish of the Claw Clan 10%, Runed Ore of Aim 10%) that could bring it to +105% (30 Archery training + 25 from Path of the shield + items). If there's a cap I'd give the items to somebody else.