All jobs on one does the story tie it together

[Naria]

There are actually are few instances for a job/class you have leveled being referenced in questlines (not just the MSQ).

For instance, I remember when I did the quest to unlock Lost City of Ampador, all of the Padjal characters acknowledged that I was a whm and A-Trowa Cant's heir, regardless of my current job. I seem to recall another time in Heavensward when dealing with the weaver's guild the guildmaster acknowledged I was a weaver even though it was not a weaver quest.

[Belhi]

There are actually quite a few small references throughout the MSQ where characters recognise your Job, particularly when you interact with someone related to your Job such as the Senna siblings for WHM or Y'Mhetra as a SMN.

As for a Job referencing that you also pursue another job, the only instance I can think of is in the ARM story quests where the guild master sends you to speak to the other guild masters and they reference make some comment if you already have levelled their craft.

[LarienTiwele]

One of the mentions many will forget are even like the Odin line where if you have WHM up... the Cutscene after Odin fight quest mentions the girl from the CNJ quest even. There are many small instances like those, but no really major ones.

[Niwashi]

I never got the feeling from story that each guild new I was going around picking up all the arts of combat.

Well, ever since when we complete our first level 10 class quest and our guildmaster tells us we're adept enough to join other guilds and learn their classes as well, I've assumed it's fairly common for adventurers in Eorzea (besides just ourselves) to at least dabble in a wide range of combat techniques. It's possible that, as WoL, we might be unusual in excelling at all of them (well, for those players who do), but it's more a matter of degree than the pattern itself being unusual.

[bswpayton]

Well,

I get the basis now , I think what i forgot was the adventurer part and have just looked at myself more in the sense of my job. I guess my main thing is more so just wishing the logic behind the whole I can literally go from doing fire ball cast as a blm to using my fist and feet as a monk. I guess for me coming here from a game like swtor, I just couldn't image solo being able to become a jedi, are luke being a smuggler. So while I love the system because it gives everyone a chance to do every job without having to go through msq. . Its been enough to me to make alts to explain it better in my own mind. . For instance my current main is whm, blm, summoner, scholar , bard because it turns into a bow mag basically, and I will do astro another magic class and ill tank as a drk because it seems like a really magic based tank. Just seems all jobs on one doesn't fit my roleplay to well cause some jobs are very night and day with each other.

[Naria]

Ah well if it is a lore issue, it is established by the lore that aether use is ubiquitous in Eorzea (and is something exceptional about the region) . The few characters that they introduce as being completely unable to use aether/magic actually have to be justified as to why they can't. The Star Wars analogy is not quite accurate because in this game almost everyone, player character or npc, can use "the Force". It is a bit of a spoiler but even the melee jobs use aether in someway, it is just used in simpler way. I just think of this use not constituting a "spell" as it doesn't draw down the character's mp. Basically while almost everyone in Eorzea can use aether/magic but not everyone has the talent, education or inclination to be a mage. So if you want to do all jobs on one character, you could use that to justify it.

As far as how quickly you can learn other jobs--part of that is simply that the Warrior of Light is exceptional but part of the reason could also be from the use of soulstones which do contain memories and impressions from previous users. You could say even effect you physically-- gameplay-wise the primary stats for a certain job are all boosted by the soulstone. For RP you could justify a character being both an skilled melee and a mage by using the soulstone if you wanted.