revert some iter patches

originally patched (badly) in https://bitbucket.org/anny-fm/piston-lp/diff/piston.tidal?diff2=a604d7e4795b&at=master#Lpiston.tidalF282T251

it seems that iter goes a bit funny when combined with smash, but works fine in itself...

snippets/p3shard

@@ -5,7 +5,7 @@
 # expand-env: (yas-indent-line fixed)
 # --
 -- @p3shard
-d'shard $ -- iter 5 . density 2 $ -- (1)
+d'shard $ -- iter 4 . density 2 $ -- (1)
   -- (p2sharda)
   (0.5 <~) $ ((1/16) <~) $ chop 16 $ s "[${1:ice} [~ $1] ~ ~]/4"
   # gain 0.7 -- (0) 0.7 (1) 0.6

snippets/p4shard

@@ -7,7 +7,7 @@
 -- @p4shard
 d'shard $
   -- whenmod 7 3 (density (5/4)) $ -- (1)
-  within (0.5, 0.75) (iter 5) $ whenmod 3 2 (slow 2) $ slow 8 $ every 2 rev $
+  within (0.5, 0.75) (iter 4) $ whenmod 3 2 (slow 2) $ slow 8 $ every 2 rev $
   striate 128 $ s "[${1:ice} ${2:plode}]*2" -- (2) ice wtsn
   # cutoff 441 -- 0.02 * (44100/2)
   # resonance 0.001