funny, i don't recall seeing you in any of my intellectual property classes at UC. which firm do you practice with? all kidding aside, your assertion is not entirely accurate. the "calculus" as you call it is a lot more complicated. firstly, there's always the risk that one of the parties will institute separate proceedings in the pto to have one or more patents invalidated. and actually, it's not as hard as one might think given the crowded nature of prior art in the cell phone field. no patent, no cross licensing, no revenues. this is essentially what happened to apple with its intellectual property battles with microsoft in the late 80s. apple rolled the dice and lost control of the look and feel of its mac operating system making it possible for ms to attain dominance. no revenues, no royalties, nada. if indeed, the equities between apple and htc/palm are as you describe, then perhaps apple could come out on top. but i haven't seen the specific infringements being asserted. further, don't forget that nokia is suing EVERYBODY for infringement of hundreds of patents for all aspect of software and hardware design. knowing apple's cavalier attitude towards patents and trademarks, it occurs to me that they could be in serious trouble here. the htc suit is probably a side skirmish designed to provide leverage with the suit with nokia (by having apple's priority vis-avis htc and palm resolved in its favor), but without reading the pleadins in all these cases, it's impossible to say.
I went to SCU (Chisum was my professor, in fact), and I am with (EDIT: a very very large Chicago-based international law firm). What firm are you with?
p.s.: invalidity? all claims of what, 10 patents? really? Given the secondary considerations of non-obviousness? (and the fact that no one can cite any 102 art?) That's quite a bit of speculation. Go read the patents before you speculate.