It appears you're dealing with a high-pressure rock with cumulus FeTi-oxides that originated from a low-degree melt. Your total mt+hm is too high by experimental standards. If you remove a total of 6% (cumulus mt+hm[from mt] combined) you'll end up with a primary-looking melt with a SiO2 content of ~46 wt.% on an anhydrous basis at ~10.8 wt.% MgO. This would require a melting pressure between 10 and 15 kb at F ~5%. Have a look at Klein & Langmuir, 1987, JGR 92, 8089-8115, their Fig. 13b.
Dimitri
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