I am having a blast and you will too!
This is what I do, forgive me for talking this out so much, I'm still figuring it out. In my system I can have my BK and HLT going at same time, I'm doing 10 gallon batches in keggles. So with that in mind I recirculate my HLT water through the coil(my probe is on the exit of coil) and back into itself (about 13 gallons) and heat it to 3 degrees above my desired mash temp. At the same time I have my strike water heating in the BK (for a 10 gallon batch) and bring it to 20 degrees above desired mash to account for loss from hoses, grain and cold MLT. If my MLT is preheated it's about 15 degrees over mash temp. So when I transfer my strike water over and dough in I just move my hose from the HLT to the MLT out and start recirculating through the coil and into the top of the MLT and the temp stays right on target for the duration (at least for my last brew!). At the end of my mash I have a process that ramps up the temp to mash out which takes about 5 minutes to come up to temp, i'm running full open at this point. This then leaves me with tons of water in the HLT at temp for my sparg as well.
Hope this helps, I think it just takes a few brews to get everything dialed in.
Just read your other post. From all the reading I've done on these forums, I don't think you need to stress about the difference as long is it's consistent.