Quiet[Remove["Global`*"],{Remove::rmnsm}];Print["Mathematica $Version = “",$Version,"”"];Print["Execution started at = ",DateString[DateList[],{"Hour",":","Minute"," on ","DayNameShort"," ","Day"," ","MonthNameShort"," ","Year"}]];

Hyperlink["http://mathematica.stackexchange.com/questions/251145/simplify-for-precision"]

clD={(distV^4) (((-1+nAC))^4) (((-1+nAR))^4) (((-1+nDR))^4)+8 (distV^3) (((-1+nAC))^4) (((-1+nAR))^3) (((-1+nDR))^4) r+8 distV (((-1+nAC))^2) (-1+nAR) (((-1+nDR))^2) r ((((-1+nDR))^2)-4 (((-1+nDR))^2) r+4 (1-(-2+nDC) nDC-2 nAC (((-1+nDR))^2)+(nAC^2) (((-1+nDR))^2)+2 (-2+nDR) nDR) (r^2))+((((-1+nDR))^2)-4 (((-1+nDR))^2) r+4 (1+(nDC^2)+2 nAC (nDC-nDR) (-1+nDR)+(nAC^2) (((-1+nDR))^2)-2 nDC nDR+2 (-1+nDR) nDR) (r^2)) ((((-1+nDR))^2)-4 (((-1+nDR))^2) r+4 (5+(nDC^2)+2 nDC (-2+nDR)+(nAC^2) (((-1+nDR))^2)+2 (-3+nDR) nDR-2 nAC (-1+nDR) (-2+nDC+nDR)) (r^2))+2 (distV^2) (((-1+nAC))^2) (((-1+nAR))^2) (((-1+nDR))^2) ((((-1+nDR))^2)-4 (((-1+nDR))^2) r+4 (-6 nAC (((-1+nDR))^2)+3 (nAC^2) (((-1+nDR))^2)-(1+nDC-2 nDR) (-3+nDC+2 nDR)) (r^2))+a (-4 ((distV^3) (((-1+nAC))^4) (((-1+nAR))^3) (((-1+nDR))^4)+2 (distV^2) (((-1+nAC))^2) (((-1+nAR))^2) (((-1+nDR))^2) (2-(-2+nDC) nDC-6 nAC (((-1+nDR))^2)+3 (nAC^2) (((-1+nDR))^2)+3 (-2+nDR) nDR) r+distV (((-1+nAC))^2) (-1+nAR) (((-1+nDR))^2) ((((-1+nDR))^2)-4 (((-1+nDR))^2) r+4 (1-3 (-2+nDC) nDC-6 nAC (((-1+nDR))^2)+3 (nAC^2) (((-1+nDR))^2)+4 (-2+nDR) nDR) (r^2))+2 r ((((-1+nDR))^2) (2+(-2+nDC) nDC-2 nAC (((-1+nDR))^2)+(nAC^2) (((-1+nDR))^2)+(-2+nDR) nDR)-4 (((-1+nDR))^2) (2+(-2+nDC) nDC-2 nAC (((-1+nDR))^2)+(nAC^2) (((-1+nDR))^2)+(-2+nDR) nDR) r+4 (2+(-2+nDC) (((-1+nDC))^2) nDC-4 (nAC^3) (((-1+nDR))^4)+(nAC^4) (((-1+nDR))^4)-6 nDR+2 (-2+nDC) nDC nDR+(11-(-2+nDC) nDC) (nDR^2)-8 (nDR^3)+2 (nDR^4)-2 nAC (((-1+nDR))^2) (1-2 (-2+nDC) nDC+3 (-2+nDR) nDR)+(nAC^2) (((-1+nDR))^2) (5-2 (-2+nDC) nDC+7 (-2+nDR) nDR)) (r^2)))+a (2 ((((-1+nDR))^2) (2+(-2+nDC) nDC-2 nAC (((-1+nDR))^2)+(nAC^2) (((-1+nDR))^2)+(-2+nDR) nDR)+(distV^2) (((-1+nAC))^2) (((-1+nAR))^2) (((-1+nDR))^2) (2-(-2+nDC) nDC-6 nAC (((-1+nDR))^2)+3 (nAC^2) (((-1+nDR))^2)+3 (-2+nDR) nDR)-12 distV (((-1+nAC))^2) (-1+nAR) (nDC+nAC (-1+nDR)-nDR) (((-1+nDR))^2) (-2+nAC+nDC+nDR-nAC nDR) r-4 (((-1+nDR))^2) (2+(-2+nDC) nDC-2 nAC (((-1+nDR))^2)+(nAC^2) (((-1+nDR))^2)+(-2+nDR) nDR) r+4 (2+(-2+nDC) nDC (1+3 (-2+nDC) nDC)-12 (nAC^3) (((-1+nDR))^4)+3 (nAC^4) (((-1+nDR))^4)-6 nDR+10 (-2+nDC) nDC nDR+(19-5 (-2+nDC) nDC) (nDR^2)-16 (nDR^3)+4 (nDR^4)-2 nAC (((-1+nDR))^2) (1-6 (-2+nDC) nDC+7 (-2+nDR) nDR)+(nAC^2) (((-1+nDR))^2) (13-6 (-2+nDC) nDC+19 (-2+nDR) nDR)) (r^2))+a (a (((nDC+nAC (-1+nDR)-nDR))^2) (((-2+nAC+nDC+nDR-nAC nDR))^2)+4 (nDC+nAC (-1+nDR)-nDR) (-2+nAC+nDC+nDR-nAC nDR) (distV (((-1+nAC))^2) (-1+nAR) (((-1+nDR))^2)-2 (nDC+nAC (-1+nDR)-nDR) (-2+nAC+nDC+nDR-nAC nDR) r)))),4 (((-1+nDR))^2) (-1+2 r) ((((-1+nDR))^2)+(distV^2) (((-1+nAC))^2) (((-1+nAR))^2) (((-1+nDR))^2)-4 (((-1+nDR))^2) r+4 distV (((-1+nAC))^2) (-1+nAR) (((-1+nDR))^2) r+4 (3+(-2+nDC) nDC-2 nAC (((-1+nDR))^2)+(nAC^2) (((-1+nDR))^2)+2 (-2+nDR) nDR) (r^2))+a (4 a (((-1+nDR))^2) (2+(-2+nDC) nDC-2 nAC (((-1+nDR))^2)+(nAC^2) (((-1+nDR))^2)+(-2+nDR) nDR) (-1+2 r)-8 (((-1+nDR))^2) (-1+2 r) (distV (((-1+nAC))^2) (-1+nAR) (((-1+nDR))^2)+2 (2+(-2+nDC) nDC-2 nAC (((-1+nDR))^2)+(nAC^2) (((-1+nDR))^2)+(-2+nDR) nDR) r)),-2 (((-1+nDR))^2) ((distV^2) (((-1+nAC))^2) (((-1+nAR))^2) ((-2+nAC) nAC-(((-1+nDC))^2)) (((-1+nDR))^2)+(-1+(-2+nAC) nAC+(-2+nDC) nDC) (((-1+nDR))^2)+4 distV (((-1+nAC))^2) (-1+nAR) ((-2+nAC) nAC-(((-1+nDC))^2)) (((-1+nDR))^2) r-4 (-1+(-2+nAC) nAC+(-2+nDC) nDC) (((-1+nDR))^2) r+4 (-3+(((nAC-nDC))^2) (((-2+nAC+nDC))^2)+4 nDR-2 (-2+nAC) nAC ((((-1+nAC))^2)+2 nDC-(nDC^2)) nDR+(-2+(-2+nAC) nAC ((((-1+nAC))^2)+2 nDC-(nDC^2))) (nDR^2)) (r^2))+a (-2 a (((-1+nDR))^2) (-4 (nAC^3) (((-1+nDR))^2)+(nAC^4) (((-1+nDR))^2)+(((-1+nDC))^2) (-2+(-2+nDC) nDC-(-2+nDR) nDR)+2 nAC (1+(-2+nDC) nDC (2+(-2+nDR) nDR))+(nAC^2) (3+4 (-2+nDR) nDR+2 nDC (2+(-2+nDR) nDR)-(nDC^2) (2+(-2+nDR) nDR)))+4 (((-1+nDR))^2) (distV (((-1+nAC))^2) (-1+nAR) ((-2+nAC) nAC-(((-1+nDC))^2)) (((-1+nDR))^2)+2 (-4 (nAC^3) (((-1+nDR))^2)+(nAC^4) (((-1+nDR))^2)+(((-1+nDC))^2) (-2+(-2+nDC) nDC-(-2+nDR) nDR)+2 nAC (1+(-2+nDC) nDC (2+(-2+nDR) nDR))+(nAC^2) (3+4 (-2+nDR) nDR+2 nDC (2+(-2+nDR) nDR)-(nDC^2) (2+(-2+nDR) nDR))) r)),-4 ((-2+nAC) nAC+(((-1+nDC))^2)) (((-1+nDR))^4) (-1+2 r),(-1+nAC-nDC) (1+nAC-nDC) (-3+nAC+nDC) (-1+nAC+nDC) (((-1+nDR))^4)};

postScriptLike[exprsn_]:=exprsn/.{Plus->add,Times->mul}//.{add[a_,b_,c__]->add[add[a,b],c], mul[a_,b_,c__]->mul[mul[a,b],c]};

operations[psLike_]:=Module[{fiForm,reaped},
	fiForm=psLike/.{nDR|nDC|nAR|nAC->i,a|r|distV->f};
	reaped=Reap[fiForm//.{
		(* add *)
		add[i|_Integer,i|_Integer]:>(Sow[int];i),
		add[f,i|_Integer]:>(Sow[flt];f),
		add[i|_Integer,f]:>(Sow[flt];f),
		add[f,f]:>(Sow[flt];f),
		(* neg *)
		mul[-1,i]:>(Sow[neg];i),
		mul[i,-1]:>(Sow[neg];i),
		mul[-1,f]:>(Sow[neg];f),
		mul[f,-1]:>(Sow[neg];f),
		(* mul *)
		mul[Except[-1,i|_Integer],Except[-1,i|_Integer]]:>(Sow[int];i),
		mul[Except[-1,i|_Integer],Except[-1,f]]:>(Sow[flt];f),
		mul[Except[-1,f],Except[-1,i|_Integer]]:>(Sow[flt];f),
		mul[Except[-1,f],Except[-1,f]]:>(Sow[flt];f),
		(* Power *)
		Power[i,n_Integer]:>(Do[Sow[int],{Ceiling[Log2[n]]}];i),(* Fails for negative powers, which I won't need *)
		Power[f,n_Integer]:>(Do[Sow[flt],{Ceiling[Log2[n]]}];f)
	}][[2]];  (* reaped *)
	If[Length[reaped]==0,{},reaped[[1]]]
]  (* operations[] *)

SetAttributes[postScriptLike,Listable];
SetAttributes[operations,Listable];

complexity[psLike_]:=Module[
	{tallies},
	tallies=Tally[Flatten[operations[psLike]]];
	Apply[Plus,Map[If[#[[1]]===flt,#[[2]],0]&,tallies]]
]

otherAttributes={
	mul[a_,b_]==mul[b,a],
	add[a_,b_]==add[b,a],
	mul[mul[a_,b_],c_]==mul[a,mul[b,c]],
	mul[a_,mul[b_,c_]]==mul[mul[a,b],c],
	add[add[a_,b_],c_]==add[a,add[b,c]],
	add[a_,add[b_,c_]]==add[add[a,b],c],
	mul[a_,add[b_,c_]]==add[mul[a,b],mul[a,c]],
	add[mul[a_,b_],mul[a_,c_]]==mul[a,add[b,c]]
};

pSL=postScriptLike[clD//Expand//Simplify];

complexity[pSL]

complexity[FullSimplify[pSL,Assumptions->otherAttributes,ComplexityFunction->complexity]]