i'd do mp+25/refresh+1 since the delve earrings, brutal/steelflash or str earrings would be good enough or better for some ws.
No.. they simply would not.
Why?
Because +25tp bonus is a direct DMG increase resulting from a higher boost to your TP mod. For instance..
Fudo benefits greatly from higher TP.. therefore boosting its "TP" with moonshade is going to directly increase its damage.
Pretend two Samurai are in the same party, one is using Moonshade (A) and one is not (B). They both do 100 WS's. Samurai A's WSs do on average 500 more damage than Samurai B's. Over the course of 100 WSs (less than 1 delve run) Samurai A would have done 50,000 more damage than Samurai B simply because he was wearing Moonshade. Thats the difference Moonshade makes in this case.
What about WSs that do not get direct damage boosts, such a critical hit weapon skills? Well.. lets look at Drakesbane, which does not have a damage multiplier associated with higher TP values BUT WSing at high TP values does raise its crit rate.
Drakesbane
1000TP 10% crit
2000TP 25% crit
3000TP 40% crit
You gain roughy an additional 3.5% crit rate from WSing in Moonshade with TP Bonus +25.
Now.. here's the kicker:
You can wear brutal earring or some form of stat+ earring with Moonshade to boost your damage further.
This would mean that if I wear Brutal and Moonshade for Drakesbane I get +3.5% crit rate and +5% DA, which is a significantly larger DPS increase than 7% double attack and some att/acc. And as discussed above, Moonshade does not directly increase the damage dealt by drakes meaning that this is a great example to show one of its weakest effects.
For things like Fudo, or even Stardiver which benefits nicely from higher TP values, the boost is enormous.