For a fouled plug, running up and leaning is an old as old as aviation,
and very proven, method of clearing the plug I have been doing it for a
half century, works for me...
If it doesn't clear, then you taxi back in and have it serviced...
As far as all the dire warnings from the manufacturers, if you followed
their SB's to the letter, you literally would not be able to fly... Those
SB's are often cya position papers crafted by their legal department, not
engineer recommendations...

cheers ... denny

"O. Sami Saydjari"