I'd say the norm (80%) is to _NOT_ get the requested step climb in the mid-Atlantic.
I've seen YQX and Shanwick give step-ups just prior to exiting the tracks, once in radar range.
I'd say it would be better to plan at one FL across the NATs.
You may also be able to get your "better" Opt/max altitude on the next abeam track. This can usually keep the burn closer to what was planned.
Marc