That is the thing though. Many people claim here that it can be done solo. Anyway the personal story will never be truly personal because you can always invite people to join your party. And if you couldn't, much would be saying that it is a shame that you can't play with friends/people in personal story. Agree. My point was that a personal story instance shouldn't be difficult to where inviting others was a requirement rather than an option.
I followed the help from this thread pre-nerf and didn't really struggle all that much with my ranger. It is helpful if you modify your build; something that is often done for any boss fight really.
I'm just as casual. I'm guessing that Anet was banking (no pun intended) on casuals not having time to farm in which case the casuals would simply open their wallets to save tine, thus infusing the company with fresh cash.
For those of us old enough to remember, even Coca-Cola reversed themselves when they put New Coke out in stores and saw how horribly their customer base responded. Anet, there is precedence. Just saying.
You should be able to get mastery points through the story-line. I got many of mine there which enabled me to upgrade mounts which, in turn, allowed me to get more mastery points and so on...
I've had fairly good success at events asking others to not mount-kill things so that others have a chance. Granted, it shouldn't fall to some players to ask others to not wipe events. I'm hopeful that ANet will reduce the dismount damage in lower tier zones.