WowAce

/ss is a brief slash command that risks conflicts with other addons (notable SoulSpeak also uses it)

We already support /speakinspell spelled out all the way.  It should be fairly easy to add a user option checkbox to optionally disable registering for /ss in order to force using /speakinspell, and allow /ss to be used by other addons.  Reloadui would probably be required to apply the change (but it might be possible to unregister it from Ace)

I don't want to permanently remove /ss though because I like the shorthand, and I don't personally run any other addons that want to use /ss for anything.

However, in the default content (DefaultSpeeches-enUS.lua) and in the mount macro generator (templates.lua) usage of /ss should be replaced by spelling it out all the way, just to make sure that the default speeches don't conflict with disabling this option (once it's added) and properly call out speakinspell macros instead of opening the SoulSpeak GUI or some effect in another addon.

Also consider a patch function to update old saved data to replace /ss macro calls with /speakinspell macro calls.  This may also be desirable as an automated function of the GUI when you edit a speech and type in /ss macro something.  It could auto-expand it to /speakinspell macro something, similar to the way it auto-expands <newline> to \n and detects macro calls to show the /ss-macro-related buttons.

reclassified this as an enhancement instead of a defect

this kind of potential conflict with other addons is a low priority