GMS Unleashed - bugs and problems

Your chance to evade an attack is determined by your avoid stat vs the attacking mob's accuracy stat then after all of that Dodge/Avoid chance kicks in giving you a secondary 70% in the DB's case and 50% in the phantom's case to dodge the attack if you didn't initially.

When the changes were introduced in KMS for DB it was known as "chance to avoid attacks", GMS changed it to dodge, then when phantom was released decide to use the original thing despite that causing confusion within the player because one said avoid and the other said dodge. Well that and no one bothers looking at their status window when inputting sp.

Avoid % is just like Avoid % on an equip: it boosts your avoid by whatever the percent is of your base avoid + avoid you get from equips and is additive with itself.
i.e. DB w/ 1000 base avoid gains 500 from equips Dual Expert gives 15% so: 1500 * 1.15 = 1725 total avoid
Phantom w/ 1000 base avoid gains 500 from equips. Dexterous Training and Feather Foot each give 20% to the avoid stat so: 1500 * 1.4 = 2100

Besides if you leave the stat window where you can see it when inputting sp you'd notice that putting points into SS, SM, MI, MM, and Carte don't actually increase your avoid stat while putting points into Dual Expert and feather foot do. And if you take all your equips off a DB/Phantom and can find something with nothing but 100 avoid on it, no other stats the DB's avoid increses by 115 while the phantoms increases by 140.
Avoid Chance and Dodge Chance are the same thing a secondary chance to avoid attacks that you did not primarily avoid based upon the random readout from the evasion formula.
The evasion formula and you chance to evade an attak are determined with your avoid vs the attacking mob's accuracy.

The maximum chance to evade an attack based upon your avoid is supposed to be 90%. What this means is even at cap avoid when you'd normally get hit by nothing other than attacks that remove a % of hp and statuses its less that your chance to evade has been reduced and more that your chance to get hit has been increased to 10% and even then you should only be getting hit approximately 3% of the time because you have, as a DB, a 70% Dodge Chance and as a Phantom 5% because they have a 50% Avoid Chance.

TL;DR

Evasion Rate = Avoid vs Accuracy; Avoid/Dodge Chance = Additional chance to avoid attacks should the primary Evasion Rate formula fail to do so.

Dual Blades do not have dodge at all, despite what the skills say (changing the description doesn't actually change the skill) and what you may think. There's 3 stats that manipulate your ability to avoid enemy attacks, % Avoid (using the variable name 'evaR'), which affects the avoidability stat on your character stat window, increasing it by a certain percentage, % Evasion Rate ("Avoid Chance", using the variable name 'er'), which is a multiplier on your miss rate (the miss rate calculated from your avoid and a monster's accuracy), and % Dodge (they use various variables for this, I think, but 'prop' is the one they usually use), which is a secondary avoiding mechanism that activates only if you fail to miss. All 70% of DB's "dodge" is actually Evasion Rate (they all use the variable 'er'), and thus, is limited by the 90% overall miss rate cap.

Dexterous Training and Feather Foot for Phantoms is also Evasion Rate (again, using 'er', while Mist Mask and the Carte Noire boost are both Dodge), here you can see I have max Feather Foot (as well as Dexterous Training, because, well, I can't not have max for it since it's an auto leveled beginner skill):



After I've used the Dexterity Potion, I gain 100 Avoid rather than 140 as you claim I should.