Hmm, ok, for those spells that take a few minutes to retrieve, maybe it works fine. But wasn't there something about some spells taking hours? And that means your genie is gone for all that time.
The only spells that take hours are divine spells that are available through your domains but not on the sorc/wiz list. Any spell on the sorc/wiz list is minutes to retrieve; if you make it a spell known, it's rounds to retrieve. My recommendation is to generally ignore the divine casting except as a method of prestige class qualification and plan on using the sorc/wiz list almost exclusively (or, if you go Skypledged, fetch cleric and druid spells through Divine Spellpool instead.) Most of the domain spells a sha'ir has access to are either duplicated on the sorc/wiz list, inferior to a spell that's on the sorc/wiz list, or just not terribly interesting, so it's no great loss, but if you really want to take a few hours casting Find The Path you have that option.
There's also, of course, the option of sending your gen out before you go to bed and waking up with a Miracle in your pocket, which isn't bad.