Might be subjective and/or discussion.. but here goes.

I've been asked to estimate a feature for the next big thing at work. I break it down.. use story points come up with a estimate. The feature however calls for interfacing with GoDiagrams a third party diagramming component in addition to various other company initiatives.. (a whole set of 2008\_Limited\_Edition frameworks/services:). I've been tracking myself using a burn-up chart and I find that I'm unable to sustain my pace primarily due to "spikes".. [Definition](http://www.think-box.co.uk/blog/2006/01/spike.html)

I estimate for 2 points a week and then I find myself working weekends (well trying to.. end up neither here nor there) because I can't figure out where to hook in so that I can preview user-actions, show a context menu, etc. In the end I spend time making spikes that throw my schedule off-track... and decreases its value.. doesn't give the right picture.

Spikes are needed to drive nails through the planks of ignorance. But how are they factored into the estimation equation? Doing all required spikes before the feature seems wrong.. (might turn out to be YAGNI) Doing it in between disrupts my flow. Right now it's during pre-iteration planning.. but this is pushing the touchline out on a weekly basis.