Descent planning and ATC

So this is more of a hybrid question and bug and maybe a solution. I’ve been starting to notice that ATC will begin descent instructions roughly the same area as defined in the Nav Log. My question is, am I correct? Does the AI ATC use those values to determine where TOD is? Secondly, is the ATC or flight planning system calculating these values at a certain slope?

Third, if my assumptions are correct, we need to be able to edit those values somehow. The problem is since the flight planning engine makes these values, and plans them over a STAR or SID that has crossing restrictions, the planner can easily get the user and ATC into an undesirable state of being too high or too fast, or both. Perhaps when making these altitudes editable, that once a user altitude is entered, it calculates a slope looking back from that user altitude? That way, ATC knows “hey, he wants to cross this point at x feet”, and so on for every other step down.

Also we need to do something about these lagging step down altitudes. Since the AP levels off at a very slow pace, as it should, ATC will wait until the aircraft falls within that parameter. This can cause a situation again where a user will be too high to make a published restriction. Perhaps adding the clearance of “descend via the STAR” and allow the user to comply with the step downs would be better, and if they are not complied, then ATC starts barking at them?

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Gotta love it when ATC wants you at FL 220 and you are 15mi from the airport. Then wants you to descend from FL220 to 3,000 in 2 mi …LOL


I wish that we could “Request descent” like in real life, it will make life easier especially if you have constrained altitudes and or speed restrictions into the STAR, a think that AI ATC seems to completely ignore.
Supporting elements for “Request descent”.
a) RWY change due to wind change.
b) Constraints Alt and speed in STAR
c) Use of engine anti ice during descent when IFR and icing conditions that increases the engine idle position due to bleed extraction (if properly modeled) requiring a earlier TOD or more aggressive speedbrake use.

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I can’t get ATC to acknowledge that my flight plan contains an approach. I cant seem to fly any IFR route where ATC will provide any appoach/decent - I get directed to the destination airport at cruise height every time. I am an ex pilot and am familiar with the FMC’s . Reading other forums this seems to be a 2020 bug