Pping!

I'm used to spell-checks rejecting most of my words-of-the-day. I see little reason to post common words.
In today's word, henotheism, however, spell-check rejected my spelling of a more common word - worshipping. Is it only one 'p'?

No, say I. But what's the rule?

Verbs ending in ‘p’

Most verbs ending in ‘p’, after an unstressed vowel, have no doubling of that final consonant in standard received British English or American English. Here are some which follow the ‘most verbs’ rule: ‘develop’, ‘gossip’, ‘gallop’ – these become just ‘developing/developed’, ‘gossiping/gossiped’, ‘galloping/galloped’.
Even here, there are pesky exceptions: ‘worship’, ‘handicap’ and ‘kidnap’ become ‘worshipping/worshipped’, ‘handicapping/handicapped’ and ‘kidnapping/kidnapped’ in standard received British English.

Fowler's makes the point that it's worshiped and sometimes kidnaped in American English. But I find this exception to the exception of the exception a bit much. Double the last consonant when taking a suffix, except for words ending in p where the final syllable is not stressed, except for worship, kidnap and handicap, except for worship in the US. But not doubling the final letter in these words with a suffix makes the final vowel look like it should be long. I'm with the Brits on this one.