The first perk of bladesman states swords have 10% chance for a critical hit. 2 more perks increase this chance to 20%. Since mace gets 70% armor penetration for 3 perks which seems very very strong, I don't expect swords to get 20% extra critical damage ... that would be laughable. So I assume that it's 20% chance for critical hit based on the rank 1 description of the bladesman perk. With 100% extra dmg on critical hit, the average dps gain of 3/3 bladesman would be 20%. The best aproximation I can get with the limited documentation of the perks.
Bladesman 1 0005f56f 30 One-handed Armsman Attacks with swords have a 10% chance of doing critical damage.
2 000c1e90 60 One-handed Attacks with swords have a 15% chance of doing more critical damage.
3 000c1e91 90 One-handed Attacks with swords have a 20% chance of doing even more critical damage.
Maces get armor penetration = more dmg dealt
Axes get bleeding = more dmg dealt
Sword get more dmg from criticals = more dmg dealt
Improving the rate of criticals would be totaly inconsistent and the other 2 perks state this fact plainly.
Also as stated in one of the other posts, you get 35% bonus speed if you spec dw perk and pull out 2nd weapon, you don't have to use it, iron dagger will do. To summ it up 21*2/0.77/0.65 = 83 dps without getting any crits with the sword, 21*2/0.77/0.65*1.2 = 100 dps if the crit perks work as I have said.
So the difference between autoattacking warrior and spell casting destro mage is in fact 83-100 vs 112. Thing is warrior can do it indefinitelly and has full mana bar for conjurations and resto healing. He can even decide to use his stamina and throw a power attack or two in the mix if he is bored. Mage once he is out of magicka just lost his dps AND his defenses.
Let me point out problems in your equation with colors

21*2/
0.77/0.65*
1.2 =
100 dpsYeah I edited it .. sword swing 1.1 sec without dw perk. Will try to test this.
Edit : Ok the sword swing is by default 0.75 sec. That's crazy strong

Have to try again.
Edit2 : 26 swings in 20 secs ... that's 0.77 swing speed.
First - your reducing by 35% the speed of your already reduced swings (35%).
Second - your adding a value that isnt a constant in the equation. Critical have a % success rate so you cant use them in a costant dmg.
After correcting the errors you left with 21dmgx2/0,77 = 42 dmg / 0,77 = 54.5 DPS
54.5 DPS of your meele is still 2 times lower than a destro lighting storm 112.5 DPS