After spending more than 30 years in the public sector (2 different state DOT's), I would strongly suggest you keep an open mind about "who you can learn from." Finding P.E.'s who are willing to mentor and share their knowledge is obviously valuable, but sometimes you can learn important...
Have your contractor consider the use of a fast-setting cement in his concrete mix. Some pre-packaged mixes can achieve earlier hydration, making for less available water to produce steam. But skip-welding as mentioned earlier is also a practical way to lessen the heat input on the plate...