BEagle - apologies on two counts.
1st: I missed the line
Now apply clock factor as above;
from your paragraph about converting max drift to actual drift.
2nd: I misjudged you. I thought that as an educated and experienced pilot with examiner qualifications, you would be able to instruct without lowering your standards to sarcasm. I was obviously wrong.
The whole point of the thread was to try to educate some of those with lesser experience than yourself, who may not have heard the "rules of thumb" before. What a pity you had to be so smart a**e about it - I thought I could rely on people like you to give intelligent responses. Sorry.