Breach Wave Velocity and Arrival Times Downstream

Hi Chris,
I was one of your students at the HEC-RAS Dam Breach Computer Workshop last month. I tried visiting the blogspot at www.rasmodel.com and www.rasmodel.blogspot.com and could not get anything, but I finally got the correct address figured out as www.hecrasmodel.blogspot.com , so you might note the correct address to make sure confused souls such as myself don't get lost in the search for the truth...
And speaking of the truth, I am trying to get the bottom of truth on reconciling velocity of flows and breach wave arrival times. I am wondering how should flow velocities for a certain duration for the breach wave moving down the channel compare to travel time averages along with distance the wave has travelled downstream.
What I am trying to do includes developing a standard TR-60 breach hydrograph used in HEC-RAS Boundary Condition to generate a flow downstream from the breached structure. We want to estimate the arrival time for the breach wave at various crossections and bridges downstream. The time to peak for the hydrograph plots is not given in too mush detail and for a limited number of crossections. I'm not real clear on how to double check these times and distance travelled downstream against velocity.
I have channel velocity, total velocity, not to mention velocity in the right and left overbanks.
Do you have a preference between channel velocity and total velocity when estimating the movement of the breach floodwave downstream; or some other means to estimate it??
The velocity for the MAX WS is significantly higher than for other time steps listed so is it a good measure of the average velocity for the breach flood wave as it moves downstream with velocity also changing according to the width of the floodplain?
Travel Time Average for each crossection in the data table seems to be listed in reverse as the time it takes the wave to travel to the crossection furthest downstream. So the most upstream crossection has the longest time and the crossection furthest downstream has a time of zero. Do you invert these values to estimate Travel Time Average for the wave moving downstream?
Do you have any suggestions on what information to use and how to use it to estimate breach wave arrival times as it moves through the crossections downstream? Do you have any suggestions on what velocity values to use that would correlate well with the distance travelled to the crossection divided by the wave travel time to the crossection as an estimate of the wave's average velocity? Should we try using a crude average of a particular velocity (i.e. Total velocity or channel velocity) for the crossections to get an average velocity for the breach flood wave as it moves downstream?? We use the breach wave travel times to develop Emergency Action Plans for the folks downstream in the the inundation zone for the breach.

Thanks for Your Help!! :^}
john