By the time Arthur Edward Waite formulated the iconic RWS tarot deck with Pamela Colman Smith, he had forsworn the magical pursuits of the Golden Dawn era and moved on into Christian mysticism. So apparently, when envisioning the Strength card, he decided to ignore the entire Tarot de Marseille tradition behind it and show the Woman trying to force the jaws of the Lion shut, thereby suppressing the animal instincts as any good Christian would do. When Paul Foster Case undertook a nominal revision of the RWS for his B.O.T.A deck, he reinstated the TdM design and once again depicted the Woman attempting to open the Lion’s mouth. Case was more Jungian in his thinking, and believed the instinctual nature should be given voice as an expression of the creativity appropriate to its Leo correspondence, and not summarily repressed. Although some more recent RWS “clones” repeat Waite’s deviation, at least one I’m aware of returns to the older design: the Pictorial Key. Here is a visual comparison of what I’m talking about; the position of the upper hand tells the whole story – Smith’s version is pushing down firmly while the others are lifting:
Personally, I’m with Case on this. Waite and Smith’s Lion looks singularly reluctant and put-upon (those carnal appetites are hard to deny!), while the others might be visiting the dentist. They appear calm and cooperative, which – unless you’re tormented like Vincent Van Gogh – you want from your muse. A few decks, the Anna K for one, show what seems to be the aftermath of the struggle, in which the two figures are coexisting in relative peace; this approach has its merits too, since true strength doesn’t need to constantly demonstrate its prowess. This gives the Lion equal billing and doesn’t display an adversarial relationship while still showing a bit of the dynamic tension that all creative pursuits benefit from. I often see this cards as one of self-mastery through channeling one’s ambitious and opportunistic demons in a productive way (Leo is, after all, a fixed sign) rather than trying to battle them to a standstill.