While using &SQL without a CURSOR will always only execute once and return one row, the SQL optimization is still dependent on the specific query - so while the cost of the non-top query is much higher, what really matters here is cost to first row.  For the example query, that will be minimal, but could be much higher in a more complicated case.

I haven't tested to see if it matters, but I see that CreateCoffee() isn't returning a %Status. 

I recall seeing this work before, but I believe it took a good amount of extra javascript work to get the ZEN drag and drop mechanisms (see doc) working nicely with the cells of tablePane. 

It is possible that a query can skip the master map completely, but only if all fields being selected are in the index and in the same form as in the master map.  

Even if all fields are in an index, indexed fields are typically stored in SQLUPPER, required for SQL comparisons, but the query must get the fields in their original form for output.  So for a SELECT *, the query will almost always need to go back to the mastermap.