Pocket is used outside a browser for offline access via a standalone application.
Portable is used in conjunction with a Portable version of a Browser (IE/Chrome/Firefox).
So, Portable is used in the same ways a user would traditionally use Lastpass, just in conjunction with a portable version of the browser. I believe that they are recommending it for that reason. Additionally, you can receive update notifications from the browsers plugin system.
Pocket is an offline standalone application, so updates are more difficult, and it doesn't integrate with web browsers, so the users flow, and many of the features of Lastpass are not available. The choice to deprecate it however is likely based on issues with update deployment.
Its notable that Portable could do all that Pocket can, and preserve the full range of features.This is I believe the reason for their initial recommendation of Portable over Pocket. Either way, they don't say why. I'd guess that no one has noticed that their messaging is inconsistent.
So, the choice between the two is based more on what you want to do with it, and whether you want to integrate with a browser (and whether you plan to bring that browser with you on a USB drive).
I'd probably go with Pocket, despite its usability issues. It doesn;t integrate with the browser, so many potential exploits are impossible from the get-go, and its codebase has not yet been deprecated. It is usable (toi the extent that its usable) on any platform without dependency on a certian version of the browser, or administrative control on the end system.
"So...I'm left confused...if I want portable access to my lastpass...what should I be doing?" Use a different product other than LastPass that has a portable version – Ramhound – 2017-06-23T18:55:44.123