Shouldn't one's first whip generally be a granary?
My guess (and give it no more weight than that) is that if you are holding off on whipping until your granary arrives, you are also starting much more slowly than you might otherwise.
1) Pottery + Bronze Working + Food + Wheel + Mining. Wheel doesn't get you much until you start hitting happy caps, and the cottages usually wait until you've got your workers and Settlers trained. In other words, these are techs that could wait.
2) While whipping with a Granary is more efficient than without, that isn't the problem the game presents to you. Instead, your choice is between whipping and not whipping. In other words, if there is a profit available, you should take it, without worrying too much about how
efficient that profit is.
3) Workers and Settlers use food for training, but because at low populations a settler produces more hammers than the food required to regrow it, you can get a slightly better conversion ratio using the whip than you do playing it straight. An of course, the whip gives you the hammers NOW, which is important if you are in a hurry.
Grow to size 2 to whip half the cost of a worker is a fairly common gambit. Under perfect circumstances, you get about 15 hammers of pure profit (usually in the form of a warrior or a scout at the start of turn 10, but it could just as easily be hammers invested in a barracks or Stone Henge).