Poking around the interwebs asking “Do you speak Agile?” I found this remarkable post: Magic Estimation.

I thought Planning Poker was the most efficient way to have those doing the work also be those who estimate the work.  But to estimate a fair sized backlog of say a hundred stories has to take several hours.  Rattling through it, just taking two or three minutes per story, well, do the math.  It’s over half a day.  If you hit any that are essential, do-first, stories that actually require a bit of digging and to and fro, well, that could be a whole day.  Still good use of the team’s time, but even so, it’s a whole day.  If you have senior management, still hearing agile as “slacker”, growling for their beloved commitment, being able to get it to them more swiftly would be impressive.  If they are growlers, chance are they are fixed-mindsetters, and like impressive things.

Even though I’d suggest you follow the Magic Estimation link above, I’m going to copy the steps for Magic Estimation to make sure I’m clear about it.

1. Start with the Product Backlog of user stories
2. Team will play, product owner will watch (and learn)
3. Lay the estimation estimation cards down on the floor, spaced out as per their values (as in the perspective picture above) e.g.

123 5  8    13     20                   40

1. Hand out user stories to team
2. Explain rules: no talking, no non-verbal communication
3. Each team member estimates, place stories at points
4. Each team member checks estimates, re-estimate and move if desired (once all own cards are down)
5. Product owner marks fall-outs (too large or keeps bouncing)
6. Discuss fall-outs until reach agreement

According to the original post, this should take, for a hundred stories, about fifteen to twenty minutes.

I’ll say that again.  100 stories –> 15-20 minutes.  Oh my!

Planning Poker would be in the region of 300 minutes.

Back in the day, when I was trying to use spreadsheets to give me range estimates thinking this to be the smart thing to do, a hundred features (pre-agile, pre-stories) I would allow a good two or three days for that kind of effort.  Looking back, frankly, I felt that even though I had a sneaking suspicion that all the work I was doing was going to be proven to be simply wrong, nonetheless, I could display my professionalism be having put so much effort into it.  My vision of those days is of me wearing the cone of uncertainty on the top of my head!

Have a go, let me know if this works for you.