What would you consider the effective top tube measurement to be? In most of my reading it seems like it starts at the top of the head tube, half-way between the front and back when viewed from the side. And from there it's a horizontal line through the middle of a seat post that continues the angle of the seat tube. Is that correct?
The reason I ask is because it appears from the graph that Fuji bikes uses the same point at the head tube but goes horizontally until the vertical line that intersects the middle of the top of the seat tube. I know mere mention of bikesdirect is polarizing but this is important as it appears bikesdirect uses the same mesurement for their geometry. Very good to know if you're ordering a bike online.
You may think the difference is trivial, but it isn't necessarily. I was looking at getting a bikesdirect Titanium bike which has a "semi-compact" geometry. Not fully compact but not a perfectly horizontal top tube either. The largest frame lists the "effective top tube" length as 585 mm. However, when I emailed BD and asked what the measurement is if you continue the horizontal line until it intersects the middle of the seat post they said it would be 605 mm. That's a difference of 20 mm, which is quite significant. Are you finding your BD bikes to be larger than you would have expected?