TFT Spell Costs vs. HOW Spell Costs

So, a quick analysis of spell costs in TFT vs, HOW.  They’re mostly the same, except that all the TFT spells that have a continuing cost have had that cost folded into the casting cost and the duration replaced with IQ + Spell Skill Level in turns, which is a pretty huge power-up.  E.g. something like Blur which in TFT costs 1 to cast, and then another 1 for each turn thereafter costs 2 in HOW and lasts for at least 9 turns, assuming you have the minimum IQ needed to cast it and 1 skill.   The summoning spells become particularly deadly, since it takes only 3 to summon a wolf to fight for you for at least 10 rounds.  Even the optional “lasts until you roll a 6 on a d6” variant is much more powerful than the TFT version.

This seems a little weird to me… for one thing, it’s likely to be more complicated in play. In TFT you’re pretty careful about having too many spells going at once, since it drains you quickly.  In HOW you can easily have a bunch, and have to track how long its been since each was cast, or roll a d6 for each if you’re using that variant.  It does make it a bit more like D&D, where spell durations are fixed, or at most adjusted for your level, but other than giving a big boost to spell-casters I’m not sure I see the advantage.  The tactics involved in deciding how long to spend your ST (or EN in HOW) on maintaining a spell are pretty interesting, in my opinion.