CUNNINGHAM STILLTHE MAN TO BEATRecent Setbacks Bo Not Mean IT. s. Olympic Hope Has SlippedHIS RIVALS HAVEimproved; thoughBy. ALAN GOULD (Associate'S Press Sports Editor)NEW YORK, March- IS.. (2P)--So far as America is- concerned, Glenn Cunningham remains the “man' to beat” in the Olympic 1500 meters—the “metric mile.”This, at least, is the consensus of our foremost track and field coaches, who' ao not consider, that this winters developments, including' a series of setbacks for the world mile -record-holder, indicate Cunningham is on the down-grade.To the contrary it is tlieir view that the great ..Kansan has “rated” himself carefully and purposely, with the Olympic tryouts and the Berlin games as his main objectives. Cunningham himself confirmed this opinion after out- • sprinting his- two indoor rivals,* Gene Venzke and . Joe Mangan, in the fantastically-run Columbian mile last Saturday night.Gene and Joe Are Better The explanation.-, for Cunningham’s defeats in most of the wiri-j ter’s big races is.- not that Glenn ■ has slipped:but that. Gene and' Joe .have, improved tremendously. Un-' til the histo-ry-making Wanamafeer ; mile at the Millroae A. A. games ; there .-wasn’t the slightest hint that.iMangan had-., a 4:11 performance-in his system, with Venzke at his -lieels1. Not since 1932 has' Venzke flashed, the form that carried him'’ to' a world record victory over Cunningham in the National A. A. XJ, 1500 meter championship. Glenn himself was- inside his own. record for that event.Just how, you may ask, does all this tend to brighten Cunningham's chances of being America’s No. 1 bidder for honors' in the Olympic classic.?' The answer, to quote Lawson Robertson of Pennsylvania, the Olympic head coach, is that Glenn, at top form, “can run a faster quarter mile or a faster half -mile than any of his rivals.”Half Mile in 1:51“Cunningham,” Robertson adds, “can do a half rnile in 1:51. That's why he holds all world, mile-running records. Glenn wasn’t in flu. best of shape earlier this winter arid he wasn’t prepared'for the hot. pace M'angan and' Venzke ' were' setting. Or, to put jt another way, Cunningham himself could ■ not sustain a fast- enough pace' totrEt