Thanks, Ioannis and Mike. Let me noodle with your suggestions for a bit.

Meanwhile, for anyone interested:

For an IF A [comparison] B THEN statement, without the appended action, the execution time at 8MHz if A and B are WORDs appears to be about 22-24us; if A and B are BYTEs, it appears to be about 5-6us. These numbers are not down to a gnat's whisker; they are as measured on my scope (Tektronix 465M).