On the boat speed question . . . there is a sweet spot, which depends on crew strength, wind and wave conditions, boat capability, and
passage length.
If you sail over your 'sweet spot' you risk making a mistake and doing damage, but you do learn

one of the reasons some
learning time on a
racing boat can productive to up your game. While if you sail below your sweet spot, you are potentially increasing your exposure to bad
weather - especially off-season or in higher latitudes.
In this case . . . the crew is honestly pretty weak. They have one excellent sailor, and one tropical milk run sailor, a couple helpers, and an infant. So, let's say 1 1/2 'real' sailors given the conditions and the boat. That means fatigue, which lowers your sweet spot speed.
The boat has speed potential, especially reaching. But it is overweight. And it needs to be reefed to the gusts, and it is gusty, and it rewards alert attentive sailors and they have probably been somewhat fatigued. And finally, it prefers flat
water . . and it is unclear to me how bumpy the
water actually is (the pics they posted don't make it look too terrible). So, it is not perfect conditions for the boat, but it is not so very far from a mom and pop doing adventurous world cruising, so it is a useful benchmark.
The conditions have been unsettled and squally and strongish. That will all lower your speed relative to your polars (vs the same sustained speed in settled flatter water). But they have had enough wind and pretty decent angles the past few days to push the boat along. And the pictures they have posted don't show a horrible sea state. That all would agrue for a faster sweet spot than they have been doing.
But, beyond those basics, there is currently another over-arching
weather priority, which is they need to go slow enough to slot in behind the secondary low on the 21st, but fast enough to get above the high-pressure break zone. That means, right at the moment, they have a specific target speed range based on their routing plan, which they are pretty much just exactly hitting. Right at the moment, they don't want to go too fast (or they run into stuff in front of them) but they equally don't want to go too slow (or they get caught). . . . and they are doing it just about exactly right.
I personally had expected the boat to naturally scoot along a bit faster without too much stress or effort... but I have concluded my expectations were simply too high again given all that is going on here.
I have confidence they have been doing this close to exactly right so far, given all they are dealing with. Those who know me, know I don't give praise easily/often . . . but I have been impressed by these guys. I like they stepped up to do something out of their comfort zone, I like the team they put together (because they were honest enough to know they needed help), and I like their attitude and execution so far.
This is a bit of a marathon, and we are only in the early stages.