Your using a Trish so I'm assuming Star Diver, meaning +750 TP Bonus along with Fotia Belt + Gorget. Stardiver's TP growth isn't quite linear, going from 1K to 2K doesn't double it's damage and the above mentioned bonus's are static regardless of TP value.
Here is the TP Values
0.75 1.25 1.75
Adding Fotia belt+gorget (200/1024) we get +0.1953125
0.9453125 / 1.4453125 / 1.9453125
Going from 1K to 2K is a 52% increase while requiring more then double the swings (9 instead of 4 on a 5-hit, 8 instead of 7 on a 4-hit), the WS is a static 2s delay which is longer then the 1.5s delay on the attack rounds.
Adding Tp Bonus makes it an even worse thing to do.
At 1K it's +0.375 TP (750 TP Bonus)
At 2K it's also +0.375
TP Bonus stops meaning anything past 2K so not going to bother and instead focus on 1K vs 2K "holding TP".
1.3203125 / 1.8203125
That's a 37.86% increase for double the number of hits.
Without counting MA (I can do that if i have your total MA amounts to figure out the average hits per round) this is the time for both 1K and 2K.
WS = 2s
480 * .20 = 96/60 = 1.6s per swing.
5-hit = 2 + (4 * 1.6) = 8.4 seconds to 1K
5-hit = 2 + (9 * 1.6) = 16.4 seconds to 2K (95% longer wait)
4-hit = 2 + (3 * 1.6) = 6.8 seconds to 1K
4-hit = 2 + (7 * 1.6) = 13.2 seconds to 2K (94% longer wait)
So with your set your looking at a 94% longer cycle time for only 37.86% increase in WS damage, effectively you are severely nerfing your own damage by deliberately waiting.
Now if those times look big, it's because I'm using 0MA and we all have MA. MA lowers the effective cycle time by reducing the number that gets multiplied by the hits.
AAPR = Average Attacks Per Round
5-hit = 2 + (4/(AAPR) * 1.6)
So with 50% you get 1.5 AAPR
5-hit = 2 + ((4/1.5) * 1.6) = 6.26 seconds to 1K averaged.
Most DD's should be aiming at about 1.8 AAPR + 5-hit before buffs, the exact values different for each job and gear build, that's just a rule of thumb which seems to balance out the numbers for optimal WS spam on a buffed DD.
https://www.ffxiah.com/forum/topic/31534/math-oax-multi-attack-and-you/
Download this spreedsheet to figure out your own AAPR.
https://docs.google.com/spreadsheets/d/1Zv6C1D04LxwjEE_464C4_Hv9eYqtaezQKfCcfWafwZc/edit#gid=0