I highly doubt the protein is giving you frizz. The only thing is I'd add enough moisture to take the "crispness" out of your hair, sounds like you've already been doing that. Your hair can get a little more frizzy if it's also crispy, but if it's not crispy it's not the protein that's giving you frizz. Be careful in how much moisture you add back though. Fine hair can get very easily over-condition, so you'll want to add moisture back after a PT but not so much that it undoes what the PT did in terms of protein-moisture balance. I have this issue frequently. My hair is never dry nor crispy, and all my products have protein (plus I add CNPF to my protein ROs) and I do PTs weekly! I just use non-stripping low-poos and good leave-in conditioners. I haven't DTed in months and I haven't needed it.

Honestly it sounds like a buildup issue to me. Is Joico KPak the only PT you've been doing? I'd recommend not doing this one, and doing a "cleaner" PT like the gelatin PT. KPak has mineral oil which could be building up. If you want purchasable PTs I'd recommend the Spiral Solutions one.

Check the Pantene product and any other product for polyquats. Many curlies have severe buildup issues with these and need sulfates to remove them (with 4, 7 and 10 being the biggest offenders).
fine - normal porosity*?- medium density - normal elasticity. Hard water. SoCal.
*Used to be low-porosity, but I lightened my hair 1-2 shades, so I may be normal-porosity now.

New climate! Current favorites:
Low-poo: CJ Gentle Cleansing Shampoo, Giovanni SaS
RO: V05 Kiwi Lime
Styler: UFD CM (old formula), FSG + CNPF
PT: CJ Repair Me, IAgirl's gelatine

Experimenting with: JC Confident Coils, JC Rockin Ringlets, CJ CIAB, gelatin gel

iherb discount code: CFN646