Ah, now I see what you mean. I misunderstood.Suppose you have 2 short swords.
You hit on a 3+, because you awesome, and you crit on a 19+. You have trivantage on all attacks.
You hit 99.9% of your attacks (!) with trivantage.
Method 1: Use sneak attack on first hit regardless.
Method 2: Make first attack. If it is a crit, use sneak attack. If not, save it for possible second attack.
Method 1 gives you 0.271271 sneak attack crits, 0.999999 sneak attack hits (or better), 0.542 crits and 1.98 hits.
Method 2 gives you 0.468559 sneak attack crits and 0.999729 sneak attack hits, 0.542 crits and 1.98 hits.
Method 2 gives you better DPR, clearly.
Basically, method 2 is when you are so certain of hitting, a mere hit on your first attack isn't worth burning your sneak attack for.
Method 1 is when your chance of missing on 2nd attack is high enough compared to your chance of hitting on 2nd attack that if you can unload your sneak attack on a mere hit, you should do it.
You should use method 2 when miss chance < crit chance basically.
Crit chance with Champ 3 is 0.271, without is 0.142625. With trivantage, those miss rates correspond to a 14+ (.65^3=27.45% miss chance) and a 12+ to hit (.55^3 = 16.64% miss chance) respectively.
Yup just realized that while thinking about this over dinner. I’ll fix later.So 20 dex +6 proficiency (+11 to hit) against AC 14 (hit on a 3+).
Level 20, Champ 3/Rogue 6, twf style.
99.9% hit chance. I'll call that 1.0 because lazy.
Your attack deals 1d6+5 damage, offhand 1d6+5, plus 9d6 sneak attack damage.
Base is 11d6+10 = 48.5 damage. You have a 27.1% crit chance for another 10d6 or +9.485, sum to 57.985 DPR, and an offhand 27.1% crit chance for +0.9485 DPR, a total of 58.9335 DPR.
With crit fishing your sneak attack crit chance becomes 0.468559, for 14.7596085 DPR, plus 0.542 * 3.5 = 1.897 from weapon crits, totaling to 65.1566085 DPR.
You had Champ 3/Rogue 17 at 58.9 DPR (matching) AND Rogue 20 with crit fishing at the same.
So your math seems off. (a) because I think I'm right, and (b) because you aren't showing a change.
I neglected a 0.002 miss chance, but that won't make that much of a difference.
Ok used your debugger. Your crit fishing is not using SA on the main hand if it crits.
That costs you a bit of DPR.
Also you are missing auto-hit on a crit.