Oh I think he is.  Why?  Because he uses them on a regular basis now.  In the early books he rarely used them and said he sucked at doing them.  Veils are not a natural skill for him like they are for Molly, Justin didn't seem to push them as a skill, Eb didn't seem interested or was under orders not
to hone sixteen year old Harry's skills in the three years he lived with him under the Doom as apprentice.  So he was never taught the skill beyond the basics and feel the need to practice it. Training Molly, he may have learned from her doing her thing naturally. Or more likely he worked harder at the skill because he had to keep on top of it to work with her.  No, he may never reach Molly's level, but he is decent at them now, and will get better as time goes on.  Face it, if you have a couple of hundred years to practice a skill, over time you will get rather good at it.

"Good" is relative I suppose. He's not incompetent at them, and he has a tendency to underrate his abilities, or at least err on the side of caution with how he rates them.

But nevertheless, he's not a finesse-focused wizard, in the way he describes Molly or Carlos, or even Ebenezar, who's both finesse and power. Teleportation is presented as something that requires finesse, rather than power (as Marcone can do it despite himself not being magically inclined, via Namshiel). It doesn't sound like something that someone who's merely competent at other tricky magic, like glamour, veils, mind magic and such, would be particularly good at.

That doesn't mean he doesn't give it a go. If he does though, I doubt it'll be the sort of straightforward power up that he can make easy use of at all times, the way we see Marcone, Drakul or Mab use it as a massive tactical advantage. It sounds more like something he'll use at great risk to himself as an act of desperation - eg he's trapped in a location that he can't otherwise magic his way out of, or he needs to get somewhere he can't otherwise reach. And it'll give him a mild aneurysm, or ruptured internal organs or something, that requires him to recuperate for weeks (after he's saved the day), and decide never to use it again.

Harry still isn't particularly good at veils 10 years later (or however long it's been).

It sounds like some extremely finnicky magic.

Also, the way things were described was that Marcone did "translocation". Harry belaboured the point a bit, talking about how it was bordering on forbidden, and extremely dangerous. Drakul's teleportation, however, wasn't dwelled upon.

I don't think you can say it was a matter of urgency in the prose. They were both life and death situations, with the fight against the Titan certainly more crucial.

Another one mentioned was Mab's. When Corb tosses the head of the Gwynn ap Nudd to Mab, tantmount to a declaration of war on the Accorded Nations by itself, and insults her, Harry describes her movement. She sort of just appears in front of Corb without passing the space in between. This sounds more like Drakul's movement - sufficiently powerful beings sound like they can simply will themselves about the place. Just as Ferrovax or Odin smush Harry to the ground with pure will, they seem to have reality warping powers that allow them to teleport around the place.

I wonder if it'll be a bit like Harry's "Be" spell, where he manifests in Ghost Story. It won't be a new skill, so much as a set piece spell he uses to accomplish a particular goal. It will involve a huge amount of risk, or he won't be very good at it.

Him reappearing without his clothes on, or inside his wedding cake, would be very much on brand.

Please no... They would be.... Ugh.
On topic, I still have no explanation why Namshiel can sling so much power around using a "plain old vanilla" man like Harry describes Marcone. If the Fallen could do that then they'll not need any practitioners to carry them around. Supposedly, most what they can do is teaching techniques and turbo boost using Hellfire, so the energy isn't coming from them, but from the host. Remember that Tessa was described as a sorceress. With presumably centuries of tutoring from Namshiel. Still, her combat repertoire was quite limited. Harry soulgazed Marcone and shook his hand. Nothing.

Hello.

I'm new.

One could imagine it working a bit like the raid on Hades' Vault.
Maybe Vadderung can't give Murphy back, but she could be stolen. He does the narrative version of tripping and dropping the keys to Valhalla, says "I sure hope I didn't drop anything important." before scurrying off, studiously avoiding meeting Harry's eyes behind his bad veil.