Get off his back!
The ventolin 60-100m calculator is as good, if not better than most of the other calculators out there; there are always going to variables that straight can't account for.
There are altitude conversions; altitude affects athletes differently.
There are wind conversions; mass, wind direction and wind consistency have different affects.
There are many race performance predictors. I would imagine someone like Dixon, Coe or Webb's 800PR is a poor predictor of what they could do in a 10K. (Some over perform the math and some underperform.)
[I's ok if things don't alway add up.] I can show you Kenyans that defies all of the predictors of why they are so good, such as growing up at altitude, consistent running at a young age, V02max, etc. Btw, Kenya use to produce very good 400m runners.
Ventolin 60/100 calc, just like all of them, works most of the time, but there will always be variables and outliers. The conventional wisdom is that athletes who are very ballistic/explosive, can’t maintain. This holds true most of the time, which is what we are looking for in a calculator. Case in point: When Bolt ran 9.58, he probably broke the 60m record in route. The Barber twins can explode out of the blocks with the best in the world and could also run 50x in a 400m dash.
In terms of relays, you don't need relay coaches and a lot of technique training, becasue most elite U.S. sprinters know just about all they need to know. It is just a matter of practice. This is always going to be a problem because our pro athletes don't belong to the same teams and the only time they actually run as a relay is in the Penn Relays.
We had some consistent relay resultes in the late 80s to early 90s, (Mitchell, Cason, Lewis, Burrell, Heard, Marsh, Drummond); these guys knew each and some years, 3/4th of the USA 4x1 was the Santa Monica TC. All of Jamaica's top athletes belong to 2 clubs (Races/MVP) and they run several realys a year with each other. (Although, nowadays, they run fewer than they use to.) Practice, practice, practice and get to know each others tendencies at at full speed in pressure situations. Russian and European teams run several exhibitions relays together prior to and after their Olympic team is 'fully' picked. We alreay know who the 2-3 likely relay candidates will be, have these guys start doing twice a month baton exchange practices even with out knwoing for sure who tthe relay will be.