I think your concerns are quite valid.
In the environment that I operate, the odds of needing to do a circling approach are extremely slim. I've been with my current mob for 4 years and have flown something like 3,000 sectors, without once doing a circling approach. It could be another 4 years before I do one for real.
By which time I'll have flown a minimum of 8 (assuming bare box-tick 1 per OPC) using the wrong technique, i.e. 'guesstimating' my way around the pattern.
One things for certain - when the chips are down, and the stress is up, people will revert to what they've actually been doing rather than what they should be doing.
Using the sim in this manner is reinforcing an unwanted behaviour.
CPB